CN111780889B - Method and system for synchronously measuring molecular rotation temperature and arrangement light intensity - Google Patents
Method and system for synchronously measuring molecular rotation temperature and arrangement light intensity Download PDFInfo
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Abstract
The invention discloses a method and a system for synchronously measuring molecular rotation temperature and arrangement light intensity, which belong to the field of molecular rotation dynamics and comprise the following steps: the coherent arrangement light and the probe light are sequentially utilized to act on the gas molecules to be detected, the gas molecules to be detected are induced to be periodically arranged, and then higher harmonics are generated; measuring target harmonic signals corresponding to different time delays between the arrangement light and the detection light, and fitting a change curve of the target harmonic signals along with the time delays; respectively obtaining the time delay corresponding to the local maximum value and the local minimum value of the target harmonic signal around the 1/2 rotation period; and respectively solving the combination of all the molecular rotation temperatures and the arrangement light intensities corresponding to the two time delays, drawing the combination in the same coordinate system to obtain two equal delay time curves, and taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the curves as synchronous measurement results. The invention can realize the synchronous and high-precision measurement of the molecular rotation temperature and the arrangement light intensity.
Description
Technical Field
The invention belongs to the field of molecular rotation dynamics, and particularly relates to a method and a system for synchronously measuring molecular rotation temperature and arrangement light intensity.
Background
The molecular rotation dynamics of coherent control can well connect a molecular coordinate system and a laboratory coordinate system. This property has led to many applications, such as obtaining molecular structure and orbital information, observing charge transport and even controlling chemical reactions, etc. In experiments, molecular rotation is often coupled with molecular vibration and electronic motion. To study the kinetic problems in molecular coordinate systems, it is crucial to have a deep knowledge of the distribution of the rotation of the molecules in time and space. The laser induced molecular rotation dynamics can be understood as two steps: firstly, the alignment light interacts with molecules, and molecular rotation wave packets are generated through stimulated Raman conversion, so that the molecules are transiently aligned in a narrow cone region; second, the created molecular rotation wave packet diffuses and evolves under field-free conditions, and the process has periodicity. Since the phase beat frequency of the coherent population rotation state is time-dependent, a molecular alignment phenomenon occurs near the molecular rotation period. In molecular alignment, the laser-induced rotational dynamics are mainly determined by two factors: one is the molecular rotation temperature, which determines the initial thermodynamic distribution of the rotating state. The second is to arrange the light intensity, which determines the re-population of the rotated state after the laser interacts with the molecule. Therefore, it is important to accurately measure the molecular rotation temperature and the alignment light intensity.
Yoshii et al report measuring the rotational temperature of molecules using a method based on higher harmonic generation (k.yoshii, et al, opt. lett.34,1651 (2009)). Yoshii et al work, the molecular rotation temperature was obtained from a fourier spectrum of the measured time-resolved higher harmonic signal, with the addition of theoretical fit, assuming parameters such as alignment light intensity. Since k.yoshii et al only assume the alignment light intensity when measuring the molecular rotation temperature, and do not actually measure the alignment light intensity, the exact alignment light intensity is unknown; meanwhile, the molecular rotation temperature is measured based on the assumed intensity of the aligned light, and thus is also inaccurate.
Disclosure of Invention
Aiming at the defects and the improvement requirements of the prior art, the invention provides a method and a system for synchronously measuring the rotation temperature and the arrangement light intensity of molecules, and aims to realize the synchronous and high-precision measurement of the rotation temperature and the arrangement light intensity of the molecules.
To achieve the above object, according to one aspect of the present invention, there is provided a method for simultaneously measuring a rotation temperature of a molecule and an intensity of an aligned light, comprising the steps of:
(S1) firstly, utilizing the aligning light to act on the gas molecules to be detected to induce the gas molecules to be detected to generate periodic alignment, and then utilizing the detecting light to act on the gas molecules to be detected to generate higher harmonics;
(S2) measuring the higher harmonic signal of the target order as a target harmonic signal, thereby obtaining a target harmonic signal corresponding to a time delay between the currently arranged light and the probe light;
(S3) performing steps (S1) to (S2) for a plurality of different time delays, respectively, to obtain target harmonic signals corresponding to the plurality of time delays, and fitting a variation curve of the target harmonic signals with the time delays;
(S4) obtaining time delays corresponding to local maxima and local minima of the target harmonic signal occurring around 1/2 rotation period based on the fitting result, and recording as a first time delay and a second time delay, respectively;
(S5) respectively solving combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solved results in the same coordinate system, thereby respectively obtaining equal delay time curves corresponding to the first time delay and the second time delay;
(S6) respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, thereby completing the synchronous measurement of the molecular rotation temperature and the arrangement light intensity;
wherein the alignment light and the probe light are coherent light.
Further, the target order is an order in a higher harmonic platform region generated by the interaction of the probe light and the periodically arranged gas molecules to be detected.
Further, in step (S3), a time delay profile of the target harmonic signal is obtained by least squares fitting.
According to another aspect of the present invention, there is provided a system for simultaneously measuring a rotational temperature of a molecule and an intensity of an aligned light, comprising: the device comprises a pumping-detecting device, a lens, a gas chamber, an X-ray spectrometer and a control device;
the pump-detection device is used for generating coherent arrangement light and detection light with adjustable time delay, and the generated arrangement light and the detection light are emitted through the same emergent light path in sequence;
the lens, the gas chamber and the X-ray spectrometer are sequentially arranged on an emergent light path of the pumping-detecting device;
the gas chamber is used for containing gas molecules to be detected; the lens is used for focusing the arrangement light on gas molecules to be detected to induce the gas molecules to be detected to be periodically arranged, and then focusing the detection light on the gas molecules to be detected to generate higher harmonics; the X-ray spectrometer is used for measuring a higher harmonic signal of a target order as a target harmonic signal;
the control device comprises a fitting module and a numerical solving module;
the fitting module is connected with the X-ray spectrometer and used for obtaining a target harmonic signal corresponding to the time delay between the current arrangement light and the detection light through the X-ray spectrometer; the control device is also used for fitting the target harmonic signals corresponding to the time delays to obtain a change curve of the target harmonic signals along with the time delays, and obtaining time delays corresponding to local maximum values and local minimum values of the target harmonic signals appearing near the 1/2 rotation period based on the fitting result, wherein the time delays are respectively marked as a first time delay and a second time delay;
the numerical solving module is used for respectively solving the combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solving result in the same coordinate system so as to respectively obtain equal delay time curves corresponding to the first time delay and the second time delay; and the numerical value solving module is also used for respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, so that the synchronous measurement of the molecular rotation temperature and the arrangement light intensity is completed.
Further, the X-ray spectrometer comprises: the device comprises an ultraviolet flat field grating, a microchannel plate and a CCD detector;
the ultraviolet flat field grating is arranged behind the gas chamber, and an included angle is formed between the ultraviolet flat field grating and the higher harmonic light beam, so that higher harmonics of different orders are separated in space;
the micro-channel plate is arranged behind the ultraviolet flat field grating and used for receiving higher harmonic signals of each order;
the CCD detector is placed behind the microchannel plate and used for collecting higher harmonic signals of each order.
Further, the pump-probe apparatus includes: the device comprises a laser, a first beam splitter, a delay line and a second beam splitter;
the first beam splitter is arranged on an emergent light path of the laser and is used for splitting laser generated by the laser into arrangement light and detection light;
the delay line is arranged on the propagation light path of the detection light and used for adjusting the time delay between the arrangement light and the detection light;
the second beam splitter is arranged at the intersection of the light paths of the arrangement light and the detection light and used for adjusting the propagation directions of the arrangement light and the detection light so that the arrangement light and the detection light are successively propagated to the lens.
Further, the pump-probe apparatus further includes: the first reflector group and the second reflector group;
the first reflector group is arranged on the propagation light path of the arrangement light and used for adjusting the propagation direction of the arrangement light;
the second reflecting mirror group is arranged on the propagation light path of the detection light and used for adjusting the propagation direction of the detection light.
Further, the target order is an order in a higher harmonic platform region generated by the interaction of the probe light and the periodically arranged gas molecules to be detected.
Generally, by the above technical solution conceived by the present invention, the following beneficial effects can be obtained:
(1) the invention obtains the variation relationship of the higher harmonic signal along with the time delay between the arranged light and the detecting light through an experimental fitting mode, thereby obtaining the time delay corresponding to the maximum value and the minimum value of the higher harmonic signal near 1/2 rotation period, obtains the combination of all the molecular rotation temperature and the arranged light intensity corresponding to the two time delays through theoretical calculation, and draws the equal time delay curves corresponding to the two time delays in the same coordinate system, because the time delay corresponding to the maximum value and the minimum value of the higher harmonic signal near 1/2 rotation period has obvious dependence relationship with the rotation temperature and the arranged light intensity, the invention can synchronously obtain the measurement results of the molecular rotation temperature and the arranged light intensity according to the intersection point of the equal time delay curves corresponding to the two time delays, and because the two parameters are obtained based on theoretical calculation, therefore, the measurement accuracy is high. In general, the invention can realize synchronous and high-precision measurement of the rotation temperature and the arrangement light intensity of molecules.
(2) The invention takes one order in the higher harmonic platform area generated by the interaction of the detection light and the periodically arranged gas molecules to be measured as the target order, and the signal intensity of the platform area is higher and stable, so the invention can accurately measure the higher harmonic signal, thereby ensuring that the molecule rotation temperature and the arrangement light intensity synchronously measured based on the higher harmonic signal have higher precision.
Drawings
FIG. 1 is a flowchart of a method for simultaneously measuring the rotational temperature and the intensity of an aligned light of a molecule according to an embodiment of the present invention;
FIG. 2 is a graph of the variation of a plurality of time delays and corresponding target harmonic signals and the fitted target harmonic signals with time delays according to an embodiment of the present invention; the harmonic wave signal processing method comprises the steps of (a) obtaining a plurality of time delays and corresponding target harmonic wave signals, and (b) obtaining a change curve of the target harmonic wave signals obtained through fitting along with the time delays;
fig. 3 is a schematic diagram of equal time delay curves corresponding to the first time delay and the second time delay and an intersection point of the two equal time delay curves according to the embodiment of the present invention; wherein, (a) is an equal time delay curve corresponding to the first time delay, (b) is an equal time delay curve corresponding to the second time delay, and (c) is an intersection point schematic diagram of the two time delay curves;
FIG. 4 is a schematic diagram of a system for simultaneously measuring the rotation temperature and the alignment light intensity of a molecule according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
In the present application, the terms "first," "second," and the like (if any) in the description and the drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.
In order to achieve the synchronous and high-precision measurement of the molecular rotation temperature and the intensity of the alignment light, in one embodiment of the present invention, a method for synchronously measuring the molecular rotation temperature and the intensity of the alignment light is provided, as shown in fig. 1, comprising the following steps:
(S1) firstly, utilizing the aligning light to act on the gas molecules to be detected to induce the gas molecules to be detected to generate periodic alignment, and then utilizing the detecting light to act on the gas molecules to be detected to generate higher harmonics;
in this embodiment, the gas molecule to be measured is nitrogen (N)2) A molecule; in other embodiments of the present invention, the gas to be measured can be any other gas molecule, the measurement process and N2The molecules are similar;
in the process of inducing the gas molecules to be periodically arranged, molecular rotation wave packets are generated and are arranged at intervals of Trev＝1/2Bec is exactly repeated once by itself, namely the molecule rotates for a period Trev＝1/2Bec, where c is the speed of light, BeIs the rotation constant of the molecule;
(S2) measuring the higher harmonic signal of the target order as a target harmonic signal, thereby obtaining a target harmonic signal corresponding to a time delay between the currently arranged light and the probe light;
in a preferred embodiment, the target order is one of the higher harmonic plateau regions generated by the interaction of the probe light and the periodically arranged gas molecules to be detected; because the signal intensity of the platform area is high and stable, the embodiment can accurately measure the higher harmonic signal, and further ensures that the molecule rotation temperature and the arrangement light intensity synchronously measured based on the higher harmonic signal have high precision;
(S3) performing steps (S1) to (S2) for a plurality of different time delays, respectively, to obtain target harmonic signals corresponding to the plurality of time delays, and fitting a variation curve of the target harmonic signals with the time delays;
in the present embodiment, the target harmonic signals corresponding to the obtained multiple time delays are shown in (a) of fig. 2;
in an alternative embodiment, in the step (S3), a variation curve of the target harmonic signal with time delay is obtained by least squares fitting, and the variation curve obtained by the fitting is shown as (b) in fig. 2;
(S4) obtaining time delays corresponding to local maxima and local minima of the target harmonic signal occurring around 1/2 rotation period based on the fitting result, and recording as a first time delay and a second time delay, respectively;
as shown in fig. 2 b, there are four characteristic times t within one rotation perioda，tb，tcAnd td。taIs 1/4TrevLocal minimum around, tbIs at 1/2TrevMidpoint of nearby local maxima and minima, tcIs 3/4TrevLocal maximum in the vicinity, tdIs at TrevThe midpoints of nearby maxima and minima; the four characteristic moments are independent of the alignment light intensity and the molecular rotation temperature and can be used for calibrating the time delay measured in the experiment;
(S5) respectively solving combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solved results in the same coordinate system, thereby respectively obtaining equal delay time curves corresponding to the first time delay and the second time delay;
calculating the change relation of the signal along with the time delay of the higher harmonic under a series of molecular rotation temperatures and arrangement light intensities;
in the calculation, a numerical method is used for solving a molecular rotation wave inclusion time Schrodinger equation:
wherein J is the rotation operator, ΨJM(θ, φ, t) is the wave function of the molecular rotation regime, BeIs the rotation constant of the molecule, θ and
is the direction of deflection and azimuth angle of the molecule, t is the time delay between the alignment light and the probe light, α∥And alpha⊥Are the polarizability tensor components parallel and perpendicular to the molecular axis. E (t) is the envelope of the aligned optical electric field. For equation (1), each initial rotation state | JM may be solved using a split operator method>；
Assuming that the initial rotational state follows the Boltzmann distribution, the angular distribution of the molecules varies with time
The modulo square of the weighted average wave packet can be written:
ρ(θ，φ，t)＝∑JMΓJM|ΨJM(θ，φ，t)|2 (2)
ΓJMis the initial state | JM given by the Boltzmann distribution>JM represents a wave function of the initial rotation state, E (t) corresponds to an electric field of the alignment light, a square of which is a light intensity of the alignment light, and the molecular rotation temperature determines the initial rotation state, thus at ΓJMThe molecular rotation temperature is included;
the time-varying higher harmonic signal can be represented by the following equation:
Sq(theta) is the order of a monomolecular q-th harmonic in a given directionPolar moment, which can be calculated by using quantitative scattering theory;
the harmonic signal varying with the delay was fitted by the least square method as shown in (b) of FIG. 2, and the 1/2 rotation period (1/2T) was obtainedrev) The time when the local maximum and minimum in the vicinity occur respectively
And
4.024 picoseconds and 4.388 picoseconds, respectively, noted as a first time interval and a second time interval, respectively; through theoretical calculation, finding out all combinations of the molecular rotation temperature and the arrangement light intensity, wherein the local maximum value corresponds to the time delay of 4.024 picoseconds around the 1/2 rotation period, and similarly finding out all combinations of the molecular rotation temperature and the arrangement light intensity, wherein the local minimum value corresponds to the time delay of 4.388 picoseconds around the 1/2 rotation period; an equal delay time curve obtained by fitting a combination of all the molecular rotation temperatures and the intensity of the aligned light corresponding to the first time delay is shown as (a) in fig. 3; an equal delay time curve obtained by fitting a combination of all the molecular rotation temperatures and the aligned light intensities corresponding to the second time delay is shown in (b) of fig. 3;
(S6) respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, thereby completing the synchronous measurement of the molecular rotation temperature and the arrangement light intensity;
in the same coordinate system, the equal delay time curves corresponding to the first time delay and the second time delay are shown as (c) in fig. 3;
wherein the alignment light and the probe light are coherent light.
In another embodiment of the present invention, there is provided a system for simultaneously measuring a rotation temperature of a molecule and an intensity of an aligned light, as shown in fig. 4, including: the device comprises a pumping-detecting device, a lens, a gas chamber, an X-ray spectrometer and a control device;
the pump-detection device is used for generating coherent arrangement light and detection light with adjustable time delay, and the generated arrangement light and the detection light are emitted through the same emergent light path in sequence;
the lens, the gas chamber and the X-ray spectrometer are sequentially arranged on an emergent light path of the pumping-detecting device;
the gas chamber is used for containing gas molecules to be detected; the lens is used for focusing the arrangement light on gas molecules to be detected to induce the gas molecules to be detected to be periodically arranged, and then focusing the detection light on the gas molecules to be detected to generate higher harmonics; the X-ray spectrometer is used for measuring a higher harmonic signal of a target order as a target harmonic signal;
the control device comprises a fitting module and a numerical solving module;
the fitting module is connected with the X-ray spectrometer and used for obtaining a target harmonic signal corresponding to the time delay between the current arrangement light and the detection light through the X-ray spectrometer; the control device is also used for fitting the target harmonic signals corresponding to the time delays to obtain a change curve of the target harmonic signals along with the time delays, and obtaining time delays corresponding to local maximum values and local minimum values of the target harmonic signals appearing near the 1/2 rotation period based on the fitting result, wherein the time delays are respectively marked as a first time delay and a second time delay;
the numerical solving module is used for respectively solving the combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solving result in the same coordinate system so as to respectively obtain equal delay time curves corresponding to the first time delay and the second time delay; and the numerical value solving module is also used for respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, so that the synchronous measurement of the molecular rotation temperature and the arrangement light intensity is completed.
As shown in fig. 4, in the present embodiment, the X-ray spectrometer includes: the device comprises an ultraviolet flat field grating, a microchannel plate and a CCD detector;
the ultraviolet flat field grating is arranged behind the gas chamber, and an included angle is formed between the ultraviolet flat field grating and the higher harmonic light beam, so that higher harmonics of different orders are separated in space; in the embodiment, the included angle between the ultraviolet flat-field grating and the higher harmonic beam is 6 degrees;
the micro-channel plate is arranged behind the ultraviolet flat field grating and used for receiving higher harmonic signals of each order;
the CCD detector is placed behind the microchannel plate and used for collecting higher harmonic signals of each order.
As shown in fig. 4, in the present embodiment, the pump-detecting device includes: the device comprises a laser, a first beam splitter, a delay line and a second beam splitter;
the first beam splitter is arranged on an emergent light path of the laser and is used for splitting laser generated by the laser into arrangement light and detection light;
the delay line is arranged on the propagation light path of the detection light and used for adjusting the time delay between the arrangement light and the detection light;
the second beam splitter is arranged at the intersection of the light paths of the arrangement light and the detection light and used for adjusting the propagation directions of the arrangement light and the detection light so that the arrangement light and the detection light are successively propagated to the lens.
As shown in fig. 4, in this embodiment, the pumping-detecting device further includes: the first reflector group and the second reflector group;
the first reflector group is arranged on the propagation light path of the arrangement light and used for adjusting the propagation direction of the arrangement light;
the second reflecting mirror group is arranged on the propagation light path of the detection light and used for adjusting the propagation direction of the detection light.
In this embodiment, the target order is an order in a higher harmonic platform region generated by interaction between the probe light and the periodically arranged gas molecules to be detected;
in this embodiment, the specific implementation of each module in the control device can refer to the description of the method embodiment, and will not be repeated here.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. A method for simultaneously measuring the rotation temperature of molecules and the intensity of arranged light, comprising the steps of:
(S1) firstly, utilizing the aligning light to act on the gas molecules to be detected so as to induce the gas molecules to be detected to generate periodic alignment, and then utilizing the detecting light to act on the gas molecules to be detected so as to generate higher harmonics;
(S2) measuring a higher harmonic signal of a target order as a target harmonic signal, thereby obtaining a target harmonic signal corresponding to a time delay between the present alignment light and the probe light;
(S3) performing steps (S1) to (S2) for a plurality of different time delays, respectively, to obtain target harmonic signals corresponding to the plurality of time delays, and fitting a variation curve of the target harmonic signals with the time delays;
(S4) obtaining time delays corresponding to local maxima and local minima of the target harmonic signal occurring around 1/2 rotation period based on the fitting result, and recording as a first time delay and a second time delay, respectively;
(S5) respectively solving combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solved results in the same coordinate system, thereby respectively obtaining equal delay time curves corresponding to the first time delay and the second time delay;
(S6) respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, thereby completing the synchronous measurement of the molecular rotation temperature and the arrangement light intensity;
wherein the alignment light and the probe light are coherent light.
2. The method according to claim 1, wherein the target order is an order in a higher harmonic platform region generated by the interaction of the probe light and the periodically arranged molecules of the gas to be measured.
3. The method for simultaneously measuring the rotational temperature and the intensity of the aligned light of the molecule according to claim 1, wherein in the step (S3), the curve of the variation of the target harmonic signal with the time delay is obtained by a least square fitting.
4. A system for simultaneously measuring the rotational temperature of a molecule and the intensity of an aligned light, comprising: the device comprises a pumping-detecting device, a lens, a gas chamber, an X-ray spectrometer and a control device;
the pump-detection device is used for generating coherent arranging light and detecting light with adjustable time delay, and the generated arranging light and the detecting light are emitted through the same emergent light path in sequence;
the lens, the gas chamber and the X-ray spectrometer are sequentially arranged on an emergent light path of the pumping-detecting device;
the gas chamber is used for containing gas molecules to be detected; the lens is used for focusing the arrangement light on the gas molecules to be detected to induce the gas molecules to be detected to be periodically arranged, and then focusing the detection light on the gas molecules to be detected to generate higher harmonics; the X-ray spectrometer is used for measuring a higher harmonic signal of a target order as a target harmonic signal;
the control device comprises a fitting module and a numerical solving module;
the fitting module is connected with the X-ray spectrometer and used for obtaining a target harmonic signal corresponding to the time delay between the current arrangement light and the detection light through the X-ray spectrometer; the control device is further used for fitting the target harmonic signals corresponding to the time delays to obtain a change curve of the target harmonic signals along with the time delays, and obtaining time delays corresponding to local maximum values and local minimum values of the target harmonic signals appearing near the 1/2 rotation period based on the fitting result, wherein the time delays are respectively marked as first time delays and second time delays;
the numerical solving module is used for respectively solving the combinations of all the molecular rotation temperatures and the arrangement light intensities corresponding to the first time delay and the second time delay by using a numerical method, and drawing the solving result in the same coordinate system, so as to respectively obtain equal delay time curves corresponding to the first time delay and the second time delay; and the numerical value solving module is also used for respectively taking the molecular rotation temperature and the arrangement light intensity corresponding to the intersection point of the two equal delay time curves as the molecular rotation temperature and the arrangement light intensity of the gas molecules to be measured, so as to complete the synchronous measurement of the molecular rotation temperature and the arrangement light intensity.
5. The system for simultaneously measuring the rotational temperature and the intensity of the aligned light of a molecule according to claim 4, wherein the X-ray spectrometer comprises: the device comprises an ultraviolet flat field grating, a microchannel plate and a CCD detector;
the ultraviolet flat field grating is arranged behind the gas chamber, and an included angle is formed between the ultraviolet flat field grating and the higher harmonic light beam, so that higher harmonics of different orders are separated in space;
the microchannel plate is placed behind the ultraviolet flat field grating and used for receiving higher harmonic signals of each order;
the CCD detector is placed behind the microchannel plate and used for collecting higher harmonic signals of each order.
6. The system for simultaneously measuring the rotational temperature and the intensity of the aligned light of a molecule according to claim 4, wherein the pump-probe apparatus comprises: the device comprises a laser, a first beam splitter, a delay line and a second beam splitter;
the first beam splitter is arranged on an emergent light path of the laser and is used for splitting laser generated by the laser into arrangement light and detection light;
the delay line is arranged on a propagation light path of the detection light and is used for adjusting the time delay between the arrangement light and the detection light;
the second beam splitter is arranged at the intersection of the light paths of the arrangement light and the detection light and used for adjusting the propagation directions of the arrangement light and the detection light so that the arrangement light and the detection light are successively propagated to the lens.
7. The system for simultaneously measuring the rotational temperature and the intensity of the aligned light of a molecule according to claim 6, wherein the pump-probe apparatus further comprises: the first reflector group and the second reflector group;
the first reflector group is arranged on a propagation light path of the arrangement light and used for adjusting the propagation direction of the arrangement light;
the second reflecting mirror group is arranged on the propagation light path of the detection light and used for adjusting the propagation direction of the detection light.
8. The system for simultaneously measuring the rotation temperature of a molecule and the intensity of an aligned light according to any one of claims 4 to 7, wherein the target order is an order in a higher harmonic plateau region generated by the interaction of the probe light and the periodically aligned gas molecules to be measured.
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