CN113625476A

CN113625476A - Electro-optical modulator, electro-optical modulation circuit, and optical communication apparatus

Info

Publication number: CN113625476A
Application number: CN202010377368.5A
Authority: CN
Inventors: 孙旭; 李心白; 马静言
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-05-07
Filing date: 2020-05-07
Publication date: 2021-11-09
Anticipated expiration: 2040-05-07
Also published as: WO2021223633A1; CN113625476B

Abstract

The application provides an electro-optical modulator, an electro-optical modulation circuit and an optical communication apparatus. The electro-optical modulator comprises a first capacitive impedance silicon optical modulator and a resistor; the first capacitive impedance silicon optical modulator is provided with a first electrode and a second electrode; the first electrode is used for connecting a signal source and connecting a bias voltage source through the resistor; the second electrode is used for connecting a reference power supply end. Because the effect of magnetic beads and inductance in the T-shaped direct current biaser can be realized by the resistor, namely, the isolation between the signal source and the bias voltage source is realized, the electro-optic modulator provided by the embodiment of the application does not need to be driven by the T-shaped direct current biaser, so that the size of the electro-optic modulation circuit is effectively reduced, and the integration level of the electro-optic modulation circuit is improved.

Description

Electro-optical modulator, electro-optical modulation circuit, and optical communication apparatus

Technical Field

The present application relates to the field of optical communications, and in particular, to an electro-optical modulator, an electro-optical modulation circuit, and an optical communications device.

Background

An electro-optical modulator is a modulation device that modulates an optical carrier wave according to an electrical signal, thereby loading the electrical signal onto the optical carrier wave, and is commonly used in optical communication apparatuses.

In the related art, the electro-optic modulator is usually driven by a T-type dc-bias (bias-tee). The T-type dc bias device has an rf port, a dc bias port, and an rf dc port, and the T-type dc bias device may include: capacitance, magnetic beads and inductance. The two ends of the capacitor are respectively connected with the radio frequency port and the radio frequency direct current port, and the magnetic bead and the inductor are connected in series between the direct current bias port and the radio frequency direct current port. The T-type dc biaser can load a radio frequency signal (i.e., a high frequency electrical signal) input by a signal source through the radio frequency port and a bias voltage input by a bias voltage source through the dc bias port to the electro-optic modulator through the radio frequency dc port.

However, the T-type dc bias device is difficult to integrate with the electro-optical modulator due to the large size of the magnetic beads and the inductor in the T-type dc bias device, and the overall size of the electro-optical modulation circuit in the optical communication device is large.

Disclosure of Invention

The application provides an electro-optical modulator, an electro-optical modulation circuit and an optical communication device, can solve the great problem of electro-optical modulation circuit size among the correlation technique, and technical scheme is as follows:

in one aspect, a single-ended driven electro-optic modulator is provided. The electro-optic modulator includes a first capacitive impedance silicon optical modulator and a resistor. The first capacitive impedance silicon optical modulator is provided with a first electrode and a second electrode, wherein the first electrode is used for being connected with a signal source and a bias voltage source through the resistor, and the second electrode is used for being connected with a reference power supply end.

The resistor can realize the action of the magnetic beads and the inductor in the T-shaped direct current biaser, namely, the isolation between a signal source and a bias voltage source, so that the electro-optic modulator does not need to be driven by the T-shaped direct current biaser, the size of the electro-optic modulation circuit is effectively reduced, and the integration level of the electro-optic modulation circuit is improved.

Optionally, the electro-optic modulator further comprises a second capacitive impedance silicon optical modulator, the first electrode of the second capacitive impedance silicon optical modulator also being used to connect the bias voltage source through the resistor.

The two capacitive impedance silicon optical modulators share one resistor, so that the number of resistors required to be arranged in the electro-optical modulator can be reduced on the premise of ensuring effective isolation between a signal source and a bias voltage source, the structure of the electro-optical modulator is simplified, and the cost of the electro-optical modulator is reduced.

Optionally, the first capacitive impedance silicon optical modulator and the second capacitive impedance silicon optical modulator in the electro-optical modulator are both micro-ring modulators. The micro-ring modulator has the advantages of small size, wavelength sensitivity and the like.

In another aspect, a differentially driven electro-optic modulator is provided. The electro-optic modulator comprises a first capacitive impedance silicon optical modulator, a first resistor and a second resistor, wherein: the first capacitive impedance silicon optical modulator is provided with a first electrode and a second electrode, and the first electrode and the second electrode are both used for being connected with a signal source; and the first electrode is also used for connecting a bias voltage source through the first resistor, and the second electrode is also used for connecting a reference power supply end through the second resistor.

The first resistor and the second resistor can realize the action of magnetic beads and inductance in the T-shaped direct current biaser, so that the electro-optic modulator does not need to be driven by the T-shaped direct current biaser, the size of the electro-optic modulation circuit is effectively reduced, and the integration level of the electro-optic modulation circuit is improved.

Optionally, the electro-optic modulator further comprises a second capacitive impedance silicon optical modulator; the first electrode of the second capacitive impedance silicon optical modulator is also used for connecting the bias voltage source through the first resistor; the second electrode of the second capacitive impedance silicon optical modulator is also used for connecting the reference power supply end through the second resistor. The two capacitive impedance silicon optical modulators share one first resistor and one second resistor, so that the number of resistors required to be arranged in the electro-optical modulator can be reduced.

Optionally, the first capacitive impedance silicon optical modulator and the second capacitive impedance silicon optical modulator in the electro-optical modulator are both micro-ring modulators.

In yet another aspect, there is provided a single-ended driven electro-optic modulation circuit, the circuit comprising: a signal source, a bias voltage source, a capacitor, and a single-ended driven electro-optic modulator as provided in the above aspects; the capacitor is connected in series between the signal source and the first electrode; the bias voltage source is connected with the first electrode through the resistor.

Because the electro-optical modulator in the electro-optical modulation circuit does not need to be driven by a T-shaped direct current biaser, the size of the electro-optical modulation circuit is effectively reduced, and the integration level of the electro-optical modulation circuit is improved.

Optionally, the signal source is a driving chip, and the electro-optical modulator is an electro-optical modulation chip; the driving chip and the electro-optic modulation chip can be connected in a wire bonding mode, a flip-chip mode or a chip stacking mode. Compared with the connection through a high-speed signal line, the direct interconnection mode is simple, the fan-out area of the signal line can be effectively reduced, and the size of the electro-optical modulation circuit is reduced.

Optionally, the signal source and the capacitor are integrated in a driving chip, so that the integration level of the electro-optical modulation circuit can be further improved.

In yet another aspect, a differentially driven electro-optic modulation circuit is provided, the circuit comprising: a signal source, a bias voltage source, a first capacitor, a second capacitor, and a differentially driven electro-optic modulator as provided in the above aspects; wherein the first capacitor is connected in series between the signal source and the first electrode; the second capacitor is connected in series between the signal source and the second electrode; the bias voltage source is connected with the first electrode through the first resistor.

Optionally, the signal source is a driving chip, and the electro-optical modulator is an electro-optical modulation chip; the driving chip and the electro-optic modulation chip can be connected in a wire bonding mode, a flip chip mode or a chip stacking mode.

Optionally, the signal source, the first capacitor and the second capacitor are all integrated in a driving chip, so that the integration level of the electro-optical modulation circuit can be further improved.

In yet another aspect, an optical communication apparatus is provided, the apparatus including: a light source, and an electro-optical modulation circuit as provided in the above aspect, in which a capacitive impedance silicon optical modulator has an optical waveguide; the light source is connected with the optical waveguide and is used for providing an optical carrier for the optical waveguide, and the electro-optical modulation circuit is used for electro-optically modulating the optical carrier.

In summary, the present application provides an electro-optical modulator, an electro-optical modulation circuit, and an optical communication device, where the electro-optical modulator in the electro-optical modulation circuit includes a first capacitive impedance silicon optical modulator and a resistor, and in the first capacitive impedance silicon optical modulator, a first electrode for connecting a signal source is further connected to a bias voltage source through the resistor. Because the effect of magnetic beads and inductance in the T-shaped direct current biaser can be realized by the resistor, namely, the isolation between the signal source and the bias voltage source is realized, the electro-optic modulator provided by the embodiment of the application does not need to be driven by the T-shaped direct current biaser, so that the size of the electro-optic modulation circuit is effectively reduced, and the integration level of the electro-optic modulation circuit is improved.

Drawings

FIG. 1 is a schematic diagram of an electro-optic modulation circuit using a micro-ring modulator in the related art;

FIG. 2a is a schematic structural diagram of a single-end driven electro-optical modulator according to an embodiment of the present disclosure;

FIG. 2b is an equivalent circuit diagram of the electro-optic modulator shown in FIG. 2 a;

FIG. 3 is a schematic structural diagram of another single-end driven electro-optic modulator provided in the embodiments of the present application;

FIG. 4a is a schematic diagram of a differentially driven electro-optic modulator according to an embodiment of the present application;

FIG. 4b is an equivalent circuit diagram of the electro-optic modulator shown in FIG. 4 a;

FIG. 5 is a schematic diagram of another differentially driven electro-optic modulator according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a structure of another differentially driven electro-optic modulator provided in the embodiments of the present application;

FIG. 7a is a schematic structural diagram of a single-end driven electro-optical modulation circuit according to an embodiment of the present disclosure;

FIG. 7b is an equivalent circuit diagram of the electro-optic modulation circuit shown in FIG. 7 a;

FIG. 8 is a schematic structural diagram of another single-end driven electro-optic modulation circuit provided in the embodiments of the present application;

FIG. 9 is a schematic structural diagram of a single-end driven electro-optic modulation circuit according to an embodiment of the present application;

FIG. 10a is a schematic diagram of a differentially driven electro-optic modulation circuit according to an embodiment of the present application;

FIG. 10b is an equivalent circuit diagram of the electro-optic modulation circuit shown in FIG. 10 a;

FIG. 11 is a schematic diagram of another structure of a differentially driven electro-optic modulation circuit according to an embodiment of the present application;

fig. 12 is a schematic diagram of leakage power of a high-frequency electrical signal according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of an optical communication device according to an embodiment of the present application.

Detailed Description

The electro-optical modulator, the electro-optical modulation circuit, and the optical communication apparatus provided in the embodiments of the present application are described in detail below with reference to the accompanying drawings.

Capacitive impedance silicon light is an electro-optical modulator commonly adopted in silicon photon (Si photonics) technology, such as a micro-ring modulator or a lumped mach-zehnder modulator, and the like, and the capacitive impedance silicon light utilizes a carrier bias effect to realize the electro-optical modulation function, and is widely applied to a multi-path transceiving system due to the advantage of high integration level of the silicon photon.

Fig. 1 is a schematic structural diagram of an electro-optical modulation circuit using a capacitive impedance silicon optical modulator in the related art. As shown in fig. 1, the capacitive impedance silicon optical modulator 01 needs to be driven by a T-type dc bias 02. The T-type dc bias device 02 includes: a capacitor C, a magnetic bead LB and an inductor L. One end of the capacitor C may be connected to the signal source 03, and the other end may be connected to the signal electrode of the capacitive impedance silicon optical modulator 01. The magnetic bead LB and the inductor L are connected in series between the bias voltage source 04 and the signal electrode.

The branch of the T-type dc biaser 02 in which the capacitor C is located may be referred to as a high-frequency branch, and is used to transmit a high-frequency electrical signal to the signal electrode for modulating an optical carrier. The branch where the magnetic bead LB and the inductor L are located may be referred to as a low frequency branch, and is used to transmit a bias voltage to the signal electrode, so that the capacitive impedance silicon optical modulator 01 can achieve an ideal operating state. Moreover, the low-frequency branch can present a high impedance to the high-frequency electrical signal, so that the high-frequency electrical signal can be prevented from leaking to the bias voltage source 04, that is, the low-frequency branch can achieve the isolation between the signal source 03 and the bias voltage source 04.

In the related art, the capacitive impedance silicon optical modulator 01 is generally integrated in a chip through a Complementary Metal Oxide Semiconductor (CMOS) process, and the chip may be referred to as a silicon optical chip. The signal source 03 may also be integrated in a chip through a CMOS process, and the chip may be referred to as a driving chip. However, the magnetic beads LB and the inductor L in the T-type dc bias device 02 have large sizes, so that the T-type dc bias device 02 is difficult to integrate into a silicon optical chip or a driving chip, and further the electro-optical modulation circuit has a large overall size and is not small enough.

The electro-optical modulator structure provided by the embodiment of the application does not need to be driven by a T-shaped direct current biaser, so that the size of the electro-optical modulation circuit can be effectively reduced, and the integration level of the electro-optical modulation circuit is improved.

Fig. 2a is a schematic structural diagram of a single-end driven electro-optical modulator according to an embodiment of the present application. As shown in fig. 2a, the electro-optic modulator includes: a first capacitive impedance silicon optical modulator 100 and a resistor R11. Figure 2b is an equivalent circuit diagram of the electro-optic modulator shown in figure 2 a. As shown in fig. 2b, the first capacitive impedance silicon optical modulator 100 is equivalent to a resistor R10 and a capacitor C10.

As can be seen from fig. 2a and 2b, the first capacitive impedance silicon optical modulator 100 has a first electrode P11 and a second electrode P12, the first electrode P11 is connected to a signal source, and the second electrode P12 is connected to a reference power source terminal.

The signal source is configured to provide a high-frequency electrical signal for the first capacitive impedance silicon optical modulator 100, and the first capacitive impedance silicon optical modulator 100 modulates the received optical carrier based on the electrical signal. The reference power source terminal is used to provide a reference potential for the first capacitive impedance silicon optical modulator 100. For example, the reference power source terminal can be the ground terminal GND, and the reference potential can be 0 volt (V).

In the solution provided by the embodiment of the present application, the electrical signal provided by the signal source is a single-ended signal, so that the first capacitive impedance silicon optical modulator 100 only receives the electrical signal provided by the signal source through the first electrode P11. Accordingly, the first electrode P11 may also be referred to as a signal (S) electrode. The second electrode P12 may also be referred to as a ground (G) electrode.

In the embodiment of the present application, the first electrode P11 is also used for connecting a bias voltage source through the resistor R11. That is, one end of the resistor R11 is connected to the first electrode P11, and the other end is connected to a bias voltage source. The bias voltage source is used to provide a bias voltage for the first capacitive impedance silicon optical modulator 100, so as to ensure that the first capacitive impedance silicon optical modulator 100 can be in an ideal working state. The resistor R11 can prevent the high-frequency electrical signal provided by the signal source from leaking to the bias voltage source, so that the signal source and the bias voltage source can be effectively isolated, and the normal operation of the first capacitive impedance silicon optical modulator 100 can be ensured.

In order to ensure effective isolation of high frequency electrical signals, the resistor R11 may have a resistance of kilo-ohm (K Ω) level. For example, the resistance of the resistor R11 may be greater than or equal to 0.5K Ω.

In the embodiment of the present application, the first capacitive impedance silicon optical modulator 100 is a capacitive electro-optical modulator using silicon photonic technology. Such as a micro-ring modulator. The micro-ring modulator has the advantages of small size, wavelength sensitivity and the like. In addition, the unique filtering characteristic can simplify the architecture of a Wavelength Division Multiplexing (WDM) system, and a single-fiber multi-wavelength solution is provided for a short-distance communication system.

Referring to fig. 2a, the micro-ring modulator 100 includes a micro-ring 101, a first doped region 102 located inside the micro-ring 101, and a second doped region 103 located outside the micro-ring 101. One of the first doped region 102 and the second doped region 103 is an N-type doped region, and the other is a P-type doped region.

The first electrode P11 is connected to the first doping region 102, and the second electrode P12 is connected to the second doping region 103. Alternatively, the first electrode P11 is connected to the second doping region 103, and the second electrode P12 is connected to the first doping region 102. Also, as can be seen from fig. 2a, the micro-ring modulator 100 may include two second electrodes P12 symmetrically disposed.

Alternatively, the first capacitive impedance silicon optical modulator 100 may also be a lumped mach-zehnder modulator (lumped-zehnder modulator), a microdisk modulator, a photonic crystal modulator, or other types of capacitive type electro-optical modulators that employ silicon photonic technology. The embodiment of the present application does not limit the type of the first capacitive impedance silicon optical modulator.

The structure of the microdisk modulator is similar to that of the micro-ring modulator, except that no gap exists between the micro-ring and the first doping region in the microdisk modulator, i.e. the micro-ring and the first doping region form a solid disk-shaped structure.

The embodiment of the present application takes the first capacitive impedance silicon optical modulator 100 as a micro-ring modulator as an example for explanation. As an alternative implementation, as shown in fig. 2a, the first electrode P11 and the resistor R11 are not directly connected, and the resistor R11 is connected to the doped region to which the first electrode P11 is connected, so as to connect to the first electrode P11. For example, as shown in fig. 2a, the first electrode P11 is connected to the first doped region 102, and the resistor R11 is also connected to the first doped region 102. As another alternative implementation, the first electrode P11 and the resistor R11 may also be directly connected.

Fig. 3 is a schematic structural diagram of another electro-optical modulator provided in the embodiments of the present application, and as shown in fig. 3, the electro-optical modulator further includes a second capacitive impedance silicon optical modulator 200. The structure of the second silicon optical modulator 200 is the same as that of the first silicon optical modulator 100, i.e. the second silicon optical modulator 200 also includes a first electrode P11 for connecting to a signal source and a second electrode P12 for connecting to a reference power source.

The first electrode P11 of the second capacitive impedance silicon optical modulator 200 is also connected to the bias voltage source through the resistor R11. That is, the first and second capacitive impedance silicon

optical modulators

100 and 200 share the same resistor R11.

Alternatively, as shown in fig. 3, the electro-optical modulator includes a plurality of second capacitive impedance silicon optical modulators 200, and the first electrodes P11 of the plurality of second capacitive impedance silicon optical modulators 200 are all connected to the resistor R11. That is, the first capacitive impedance silicon optical modulator 100 and the plurality of second capacitive impedance silicon optical modulators 200 share the same resistor R11.

By sharing one resistor with a plurality of capacitive impedance silicon optical modulators, the number of resistors required to be arranged in the electro-optical modulator can be effectively reduced on the premise of ensuring effective isolation between a signal source and a bias voltage source, so that the structure of the electro-optical modulator is simplified, and the cost of the electro-optical modulator is reduced.

In the embodiment of the present application, the electro-optic modulator may further include a plurality of first capacitive impedance silicon optical modulators 100 and a plurality of resistors R11. Wherein each resistor R11 is connected to the first electrode P11 of a first capacitive impedance silicon optical modulator 100. That is, the resistors R11 connected to the plurality of first capacitive impedance silicon optical modulators 100 are independent of each other.

Because the resistor is small in size, each capacitive impedance silicon optical modulator and the resistor included in the electro-optical modulator can be integrated in one electro-optical modulation chip, and therefore the multi-channel electro-optical modulation chip is achieved. For example, 8 capacitive impedance silicon optical modulators may be integrated in the electro-optical modulation chip, that is, the electro-optical modulation chip is an 8-channel electro-optical modulation chip, and can implement modulation on 8 channels of optical carriers.

It should be noted that the single-end driven electro-optical modulator provided in the embodiments of the present application may include a plurality of capacitive impedance silicon optical modulators of the same type. For example, both may be micro-ring modulators.

In summary, the embodiment of the present application provides a single-end driven electro-optical modulator, where the electro-optical modulator includes a first capacitive impedance silicon optical modulator and a resistor, and in the first capacitive impedance silicon optical modulator, a first electrode used for connecting a signal source is further connected to a bias voltage source through the resistor. Because the resistor can realize the isolation between the signal source and the bias voltage source, the electro-optical modulator provided by the embodiment of the application does not need to be driven by a T-shaped direct current biaser, thereby effectively reducing the size of the electro-optical modulation circuit and improving the integration level of the electro-optical modulation circuit.

Fig. 4a is a schematic structural diagram of a differentially driven electro-optic modulator according to an embodiment of the present application. As shown in fig. 4a, the differentially driven electro-optic modulator comprises a first capacitive impedance silicon optical modulator 300, a first resistor R21, and a second resistor R22. Figure 4b is an equivalent circuit diagram of the electro-optic modulator shown in figure 4 a. As shown in fig. 4b, the first capacitive impedance silicon optical modulator 300 is equivalent to a resistor R20 and a capacitor C20.

As can be seen from fig. 4a and 4b, the first capacitive impedance silicon optical modulator 300 has a first electrode P21 and a second electrode P22, and the first electrode P21 and the second electrode P22 are both used for connecting a signal source.

The electrical signal provided by the signal source is a differential signal, so the first capacitive impedance silicon optical modulator 300 needs to receive the differential signal through the first electrode P21 and the second electrode P22. The first electrode P21 may also be referred to as a positive (P) electrode, and the second electrode P22 may also be referred to as a negative (N) electrode.

Referring to fig. 4a and 4b, the first electrode P21 is also connected to a bias voltage source through the first resistor R21. That is, one end of the first resistor R21 is connected to the first electrode P21, and the other end is connected to a bias voltage source. The second electrode P22 is also connected to a reference power terminal through the second resistor R22. That is, one end of the second resistor R22 is connected to the second electrode P22, and the other end is connected to a reference power source terminal.

In the scheme of differential driving, the first electrode P21 and the second electrode P22 are both used for receiving a high-frequency electrical signal provided by a signal source, and therefore two resistors need to be arranged to be connected with the two electrodes respectively, so as to realize effective isolation of the high-frequency electrical signal and avoid leakage of the high-frequency electrical signal. Each of the first resistor R21 and the second resistor R22 may have a resistance of K Ω. For example, the resistance of each resistor may be greater than or equal to 0.5K Ω.

In the embodiment of the present application, the first capacitive impedance silicon optical modulator 300 may be a capacitive type electro-optical modulator using silicon photonic technology, such as a micro-ring modulator, a lumped mach-zehnder modulator, a micro-disk modulator, or a photonic crystal modulator.

In the embodiment of the present application, a first capacitive impedance silicon optical modulator 300 is taken as a micro-ring modulator for illustration, and referring to fig. 4a, the first capacitive impedance silicon optical modulator 300 includes a micro-ring 301, a first doped region 302, and a second doped region 303.

Alternatively, the first resistor R21 may be directly connected to the first electrode P21, or as shown in fig. 4a, the first resistor R21 may be connected to the first electrode P21 through the first doped region 302. Similarly, the second resistor R22 can be directly connected to the second electrode P22, or as shown in fig. 4a, the second resistor R22 can be connected to the second electrode P22 through the second doped region 303.

Fig. 5 is a schematic structural diagram of another differentially driven electro-optical modulator provided in the embodiment of the present application, and as shown in fig. 5, the electro-optical modulator further includes a second capacitive impedance silicon optical modulator 400. The second silicon optical modulator 400 has the same structure as the first silicon optical modulator 300, i.e., the second silicon optical modulator 400 also includes a first electrode P21 and a second electrode P22 for connecting a signal source.

The first electrode P21 of the second capacitive impedance silicon optical modulator 400 is also connected to the bias voltage source through the first resistor R21; the second electrode P22 of the second capacitive impedance silicon optical modulator 400 is also connected to the reference power source terminal through the second resistor R22. That is, the first and second capacitive impedance silicon

optical modulators

300 and 400 share the same first resistor R21 and the same second resistor R22.

As shown in fig. 5, the electro-optic modulator may include a plurality of second capacitive impedance silicon optical modulators 400 and a plurality of second resistors R22. The first electrodes P21 of the second capacitive impedance silicon optical modulators 400 are all connected to the first resistor R21. Moreover, the plurality of second capacitive impedance silicon optical modulators 400 are arranged linearly, wherein every two adjacent second capacitive impedance silicon optical modulators 400 are connected to the same second resistor R22, i.e. every two adjacent second capacitive impedance silicon optical modulators 400 share the same second resistor R22.

By sharing the first resistor and the same second resistor with the plurality of capacitive impedance silicon optical modulators, the number of resistors required to be arranged in the electro-optical modulator can be effectively reduced on the premise of effectively isolating the high-frequency electric signals provided by the signal source, the structure of the electro-optical modulator is simplified, and the cost of the electro-optical modulator is reduced.

Optionally, the differentially driven electro-optical modulator provided by the embodiment of the present application may include a plurality of first capacitive impedance silicon optical modulators 300, a plurality of first resistors R21, and a plurality of second resistors R22. The first electrode P21 of each first capacitive impedance silicon optical modulator 300 is connected to a first resistor R21, and the first resistors R21 connected to the first electrodes P21 of the first capacitive impedance silicon optical modulators 300 are independent of each other. Accordingly, the number of first resistors R21 included in the electro-optic modulator is equal to the number of first capacitive impedance silicon optical modulators 300.

In one implementation, as shown in fig. 6, the plurality of first capacitive impedance silicon optical modulators 300 are arranged linearly, and every two adjacent first capacitive impedance silicon optical modulators 300 are connected to the same second resistor R22, i.e. every two adjacent first capacitive impedance silicon optical modulators 300 share the same second resistor R22. In this implementation, the number of second resistors R22 included in the electro-optic modulator is less than the first capacitive impedance silicon optical modulator 300.

In another implementation, the second electrode P22 of each first capacitive impedance silicon light modulator 300 is connected to a second resistor R22, and the second resistors R22 connected to the second electrodes P22 of the respective first capacitive impedance silicon light modulators 300 are independent of each other. In this implementation, the number of second resistors R22 included in the electro-optic modulator is equal to the number of first capacitive impedance silicon optical modulators 300.

It should be noted that the type of the capacitive impedance silicon optical modulators included in the differentially driven electro-optical modulator provided in the embodiments of the present application may be the same. For example, both may be micro-ring modulators.

In summary, the present application provides a differential-driven electro-optical modulator, which includes a first capacitive impedance silicon optical modulator, a first resistor, and a second resistor, wherein in the first capacitive impedance silicon optical modulator, a first electrode for connecting a signal source is connected to a bias voltage source through the first resistor, and a second electrode for connecting the signal source is connected to a reference power source through the second resistor. Because the first resistor and the second resistor can realize the isolation between the signal source and the bias voltage source, the electro-optical modulator provided by the embodiment of the application does not need to be driven by a T-shaped direct current biaser, thereby effectively reducing the size of the electro-optical modulation circuit and improving the integration level of the electro-optical modulation circuit.

Fig. 7a is a schematic structural diagram of a single-end driven electro-optical modulation circuit provided in an embodiment of the present application, and referring to fig. 7a, the circuit includes: the electro-optical modulator comprises a single-end driven electro-optical modulator 10, a signal source 20, a bias voltage source 30 and a capacitor C11. The electro-optical modulator 10 may be any one of the modulators shown in fig. 2a to 3.

Fig. 7b is an equivalent circuit diagram of the electro-optic modulation circuit shown in fig. 7a, and referring to fig. 7a and 7b, the capacitor C11 is connected in series between the signal source 20 and the first electrode P11. The bias voltage source 30 is connected to the first electrode P11 through the first resistor R11.

Optionally, the electro-optic modulator 10 further comprises one or more second capacitive impedance silicon optical modulators 200, or a plurality of first capacitive impedance silicon optical modulators 100. For scenarios in which the electro-optic modulator 10 comprises a plurality of capacitive impedance silicon electro-optic modulators, as shown in FIG. 8, the electro-optic modulation circuit comprises a plurality of capacitors C11, wherein each capacitor C11 is connected in series between the signal source 20 and a first electrode P11 of the electro-optic modulator 10.

As can be seen from fig. 8, the signal source 20 is connected to a plurality of capacitors C11, and supplies high-frequency electrical signals to a plurality of capacitive impedance silicon optical modulators. For example, as shown in fig. 8, the signal source 20 provides high frequency electrical signals to the four first capacitive impedance silicon optical modulators 100 through four capacitors C11. I.e. the signal source 20 is a four-channel signal source.

Alternatively, the electro-optic modulator 10 may comprise a plurality of first capacitive impedance silicon optical modulators 100, and a plurality of resistors R11. As shown in fig. 8, the electro-optical modulation circuit may only include one bias voltage source 30, and the one bias voltage source 30 is connected to the plurality of resistors R11 and provides a bias voltage to each of the first capacitive impedance silicon optical modulators 100 through the plurality of resistors R11. Because only one bias voltage source 30 needs to be arranged in the electro-optical modulation circuit, the circuit cost can be effectively reduced, and the circuit structure is simplified. As another alternative, the electro-optic modulation circuit may also include a plurality of bias voltage sources 30, wherein each bias voltage source 30 is connected to a resistor R11, and provides a bias voltage to a first capacitive impedance silicon optical modulator 100 through the resistor R11. The resistance R11 to which any two bias voltage sources 30 are connected is different. By arranging a plurality of bias voltage sources 30, the bias voltage of each first capacitive impedance silicon optical modulator 100 can be independently adjusted, so that the flexibility of the electro-optical modulation circuit during operation is effectively improved.

Alternatively, as shown in fig. 9, in the embodiment of the present application, the signal source 20 is a driving chip, and the electro-optical modulator 10 is an electro-optical modulation chip. The driving chip 20 and the electro-optic modulation chip 10 can be connected by wire bonding, flip chip or chip stacking. Compared with the connection of two chips through a high-speed signal line, the connection mode can not only avoid the influence of the transmission of electric signals of the high-speed signal line on the quality of the electric signals, but also effectively reduce the size of the electro-optical modulation circuit and realize the miniaturization design of the electro-optical modulation circuit.

Of course, the driver chip 20 and the electro-optical modulation chip 10 can be connected by high-speed signal lines. In addition, in the embodiment of the present application, since a T-type dc bias device is not required to be disposed between the driving chip 20 and the electro-optical modulation chip 10, compared with the related art, the routing distance of the high-speed signal line can be effectively shortened, and the loss of the high-frequency electrical signal is reduced.

In the embodiment of the present application, the capacitor C11 may also be integrated in the driving chip 20, that is, the signal source and the capacitor may be integrated in the same chip, thereby further improving the integration of the electro-optical modulation circuit.

It should be noted that the number of channels of the electro-optical modulator chip 10 may be greater than or equal to the number of channels of the driving chip 20. If the number of channels of the electro-optic modulator chip 10 is greater than the number of channels of the driver chips 20, the electro-optic modulator chip 10 is connected to the plurality of driver chips 20. For example, referring to fig. 9, if the number of channels of the electro-optical modulator chip 10 is 8 and the number of channels of the driver chip 20 is 4, the electro-optical modulator chip 10 is connected to two driver chips 20.

In summary, the embodiment of the present application provides a single-end driven electro-optical modulation circuit. The electro-optical modulator in the electro-optical modulation circuit comprises a first capacitive impedance silicon optical modulator and a resistor, wherein a first electrode connected with a signal source in the first capacitive impedance silicon optical modulator is connected with a bias voltage source through the resistor. Because the resistor can realize the action of the magnetic beads and the inductor in the T-shaped direct current biaser, namely, the isolation between the signal source and the bias voltage source, the electro-optical modulation circuit provided by the embodiment of the application does not need to adopt the T-shaped direct current biaser, thereby effectively reducing the size of the electro-optical modulation circuit and improving the integration level of the electro-optical modulation circuit.

Fig. 10a is a schematic structural diagram of a differentially driven electro-optical modulation circuit provided in an embodiment of the present application, and as shown in fig. 10a, the circuit includes: a differential-end-driven electro-optic modulator 40, a signal source 50, a bias voltage source 60, a first capacitor C21, and a second capacitor C22. The electro-optic modulator 40 may be any one of the modulators shown in fig. 4a to 6.

Fig. 10b is an equivalent circuit diagram of the electro-optic modulation circuit shown in fig. 10a, and referring to fig. 10a and 10b, it can be seen that the first capacitor C21 is connected in series between the signal source 50 and the first electrode P1. The second capacitor C22 is connected in series between the signal source 50 and the second electrode P2. The bias voltage source 60 is connected to the first electrode P21 through the first resistor R21, and a reference power source terminal (e.g., the ground terminal GND shown in fig. 10a and 10 b) is connected to the second electrode P22 through a second resistor R22.

Optionally, the electro-optic modulator 40 further comprises one or more second capacitively-impedance silicon optical modulators 400, or may comprise a plurality of first capacitively-impedance silicon optical modulators 300. For a scenario where the electro-optic modulator 40 comprises a plurality of capacitive impedance silicon electro-optic modulators, the electro-optic modulation circuit comprises a plurality of first capacitances C21 and a plurality of second capacitances C22, as shown in fig. 11. Wherein each first capacitor C21 is connected in series between the signal source 50 and a first electrode P21, and each second capacitor C22 is connected in series between the signal source 50 and a second electrode P22.

Also, referring to fig. 11, the signal source 50 is connected to the plurality of first capacitors C21 and the plurality of second capacitors C22, and provides a high frequency electrical signal to the plurality of capacitive impedance silicon optical modulators. For example, as shown in fig. 11, the signal source 50 provides high-frequency electrical signals for four capacitive impedance silicon optical modulators, i.e., the signal source 50 is a four-channel signal source.

Alternatively, the electro-optic modulator 40 may comprise a plurality of first capacitive impedance silicon optical modulators 300, and a plurality of first resistors R21. For the scenario that the electro-optical modulator 40 includes a plurality of first resistors R21, as an alternative implementation manner, as shown in fig. 11, the electro-optical modulation circuit includes only one bias voltage source 60, and the one bias voltage source 60 is connected to the plurality of first resistors R21 and provides a bias voltage for each first capacitive impedance silicon optical modulator 300 through the plurality of first resistors R21 in a unified manner. Because only one bias voltage source 60 needs to be arranged in the electro-optical modulation circuit, the circuit cost can be effectively reduced, and the circuit structure is simplified.

For the scenario that the electro-optical modulator 40 includes a plurality of first resistors R21, as another optional implementation manner, the electro-optical modulation circuit may also include a plurality of bias voltage sources 60, each bias voltage source 60 is connected to one first resistor R21, and provides a bias voltage to one first capacitive impedance silicon optical modulator 400 through the first resistor R21. The first resistors R21 connected to any two bias voltage sources 60 are different. Therefore, the bias voltage of each first capacitive impedance silicon optical modulator 400 can be independently adjusted, and the flexibility of the electro-optical modulation circuit during operation is effectively improved.

Optionally, in the embodiment of the present application, the signal source 50 is a driving chip, and the electro-optical modulator 40 is an electro-optical modulation chip. The driving chip 50 and the electro-optic modulation chip 40 can be connected by wire bonding, flip chip or chip stacking. Of course, the driving chip 50 and the electro-optical modulation chip 40 can be connected by high speed signal lines.

In the embodiment of the present application, the first capacitor C21 and the second capacitor C22 may also be integrated in the driving chip 50, that is, the signal source, the first capacitor C21 and the second capacitor C22 are all integrated in the same chip. Thereby, the integration degree of the electro-optical modulation circuit can be further improved.

In summary, an embodiment of the present application provides a differential-driven electro-optical modulation circuit, where an electro-optical modulator in the electro-optical modulation circuit includes a first capacitive impedance silicon optical modulator, a first resistor, and a second resistor, and in the first capacitive impedance silicon optical modulator, a first electrode connected to a signal source is connected to a bias voltage source through the first resistor, and a second electrode connected to the signal source is connected to a reference power source through the second resistor. Because the first resistor and the second resistor can realize the isolation between the signal source and the bias voltage source, the electro-optical modulation circuit provided by the embodiment of the application does not need to adopt a T-shaped direct current biaser, thereby effectively reducing the size of the electro-optical modulation circuit and improving the integration level of the electro-optical modulation circuit.

It should be noted that, in the single-ended driving and differential driving electro-optical modulation circuit provided in the embodiment of the present application, the bias voltage source may be directly connected to the electro-optical modulation chip, so that the setting position of the bias voltage source is no longer limited by the setting position of the T-type dc offset device, and the setting position of the bias voltage source is flexible. For example, referring to fig. 9, the driving chip 20 is disposed on a first side of the electro-optical modulation chip 10, and the bias voltage source 30 is disposed on a second side of the electro-optical modulation chip 10, where the first side and the second side are different sides of the electro-optical modulation chip 10. Therefore, the layout flexibility of all components in the electro-optical modulation circuit is high, and the overall size of the electro-optical modulation circuit can be effectively reduced.

The embodiment of the application also simulates the power of the high-frequency electric signal leaked by the signal source in the electro-optical modulation circuit. When the electro-optical modulation circuit driven by a single end is simulated, a resistor R11 adopted by the electro-optical modulation circuit is a resistance wire of 1k omega. When the electro-optical modulation circuit driven by difference is simulated, the first resistor R21 and the second resistor R22 adopted by the electro-optical modulator 40 are resistance wires of 1k Ω. As shown in fig. 12, the horizontal axis of fig. 12 represents the frequency of the high-frequency electrical signal supplied from the signal source in gigahertz (GHz), and the vertical axis represents the power of the leaked high-frequency electrical signal in decibels (dB). For a single-end driven electro-optical modulation circuit, the power of the leaked electrical signal is detected on the bias voltage source 30 side. For a differentially driven electro-optical modulation circuit, the power of the leaked electric signal is detected on the bias voltage source 60 side or the reference power supply side.

As shown in fig. 12, the power of the electrical signal leaked from the signal source is always less than-46 dB as the frequency of the high frequency electrical signal provided by the signal source varies. Therefore, according to the scheme provided by the embodiment of the application, the function of low-frequency branches in the T-shaped direct current biaser can be realized by adding the resistor in the electro-optical modulator, namely the resistor can effectively isolate high-frequency electric signals provided by the signal source, and the normal operation of the electro-optical modulator is ensured.

Fig. 13 is a schematic structural diagram of an optical communication device according to an embodiment of the present application, and as shown in fig. 13, the optical communication device includes: an electro-optical modulation circuit 001 and a light source 002. The electro-optical modulation circuit 001 may be a circuit as shown in any one of fig. 7a to 11. For example, the electro-optical modulation circuit 001 in the apparatus shown in fig. 13 may be a single-end driven electro-optical modulation circuit provided by the above-described embodiment.

As shown in fig. 13, the capacitive impedance silicon optical modulator 100 in the electro-optical modulation circuit 001 further has an optical waveguide 104, the light source 002 is connected to the optical waveguide 104 for providing the optical carrier to the optical waveguide 104, and the electro-optical modulation circuit 001 can perform electro-optical modulation on the optical carrier.

Alternatively, referring to the above embodiments, the electro-optical modulation circuit 001 may include a plurality of first capacitive impedance silicon optical modulators, or may include one or more second capacitive impedance silicon optical modulators. For a scenario in which the electro-optical modulation circuit 001 includes a plurality of capacitive impedance silicon optical modulators, the light source 002 is connected to the optical waveguide 004 of each capacitive impedance silicon optical modulator, respectively, and provides an optical carrier to each capacitive impedance silicon optical modulator, respectively.

The light source 002 may provide a plurality of optical carriers with different wavelengths for each capacitive impedance silicon optical modulator, each capacitive impedance silicon optical modulator is configured to modulate an optical carrier with one of the wavelengths, and the wavelengths of the optical carriers modulated by the capacitive impedance silicon optical modulators are different.

In summary, the embodiment of the present application provides an optical communication device, in which an electro-optical modulation circuit in the optical communication device has a small size and a high integration level, so that the integration level of the optical communication device is effectively improved.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. An electro-optic modulator comprising a first capacitive impedance silicon electro-optic modulator and a resistor, wherein:

the first capacitive impedance silicon light modulator is provided with a first electrode and a second electrode;

the first electrode is used for connecting a signal source and connecting a bias voltage source through the resistor;

the second electrode is used for connecting a reference power supply end.

2. The electro-optic modulator of claim 1, further comprising a second capacitive impedance silicon optical modulator;

the first electrode of the second capacitive impedance silicon optical modulator is also used for connecting the bias voltage source through the resistor.

3. An electro-optic modulator according to claim 1 or 2, wherein the capacitive impedance silicon optical modulator in the electro-optic modulator is a micro-ring modulator.

4. An electro-optic modulator comprising a first capacitive impedance silicon electro-optic modulator, a first resistor and a second resistor, wherein:

the first capacitive impedance silicon optical modulator is provided with a first electrode and a second electrode, and the first electrode and the second electrode are both used for being connected with a signal source;

the first electrode is also used for connecting a bias voltage source through the first resistor;

the second electrode is also used for connecting a reference power supply end through the second resistor.

5. The electro-optic modulator of claim 4, further comprising a second capacitive impedance silicon optical modulator;

the first electrode of the second capacitive impedance silicon optical modulator is also used for connecting the bias voltage source through the first resistor;

the second electrode of the second capacitive impedance silicon optical modulator is also used for connecting the reference power supply end through the second resistor.

6. An electro-optic modulator according to claim 4 or 5, wherein the capacitive impedance silicon optical modulator is a micro-ring modulator.

7. An electro-optic modulation circuit, comprising: a signal source, a bias voltage source, a capacitor, and an electro-optic modulator according to any one of claims 1 to 3;

the capacitor is connected in series between the signal source and the first electrode;

the bias voltage source is connected with the first electrode through the resistor.

8. The circuit of claim 7, wherein the signal source is a driver chip and the electro-optical modulator is an electro-optical modulation chip;

the driving chip and the electro-optic modulation chip are connected in a routing mode, a flip chip mode or a chip stacking mode.

9. The circuit of claim 7, wherein the signal source and the capacitor are integrated in a driver chip.

10. An electro-optic modulation circuit, comprising: a signal source, a bias voltage source, a first capacitor, a second capacitor, and an electro-optic modulator according to any of claims 4 to 6;

the first capacitor is connected in series between the signal source and the first electrode;

the second capacitor is connected in series between the signal source and the second electrode;

the bias voltage source is connected with the first electrode through the first resistor.

11. The circuit of claim 10, wherein the signal source is a driver chip and the electro-optical modulator is an electro-optical modulation chip;

12. The circuit of claim 10, wherein the signal source, the first capacitor, and the second capacitor are integrated in a driver chip.

13. An optical communication device, characterized in that the device comprises: a light source, and the electro-optical modulation circuit according to any one of claims 7 to 12, wherein the capacitive impedance silicon optical modulator further has an optical waveguide;

the light source is connected with the optical waveguide and used for providing an optical carrier for the optical waveguide, and the electro-optical modulation circuit is used for electro-optically modulating the optical carrier.