JPH03295471A - Dc-squid measuring instrument - Google Patents
Dc-squid measuring instrumentInfo
- Publication number
- JPH03295471A JPH03295471A JP2098340A JP9834090A JPH03295471A JP H03295471 A JPH03295471 A JP H03295471A JP 2098340 A JP2098340 A JP 2098340A JP 9834090 A JP9834090 A JP 9834090A JP H03295471 A JPH03295471 A JP H03295471A
- Authority
- JP
- Japan
- Prior art keywords
- output
- phase difference
- circuit
- filter
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000010355 oscillation Effects 0.000 claims abstract description 24
- 238000001514 detection method Methods 0.000 claims description 10
- 238000012544 monitoring process Methods 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 description 7
- 230000010363 phase shift Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 1
- 238000000087 superconducting quantum interference device magnetometry Methods 0.000 description 1
Landscapes
- Measurement Of Current Or Voltage (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、直流駆動型超電導量子緩衝素子（以下ＤＣ−
３ＱＵ Ｉ Ｄと称する）の電流−電圧特性又は磁束−
電圧特性を測定するＤＣ−ＳＱＵＩＤ測定装置に関する
ものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a direct current driven superconducting quantum buffer device (hereinafter referred to as DC-
(referred to as 3QUID) current-voltage characteristics or magnetic flux-
The present invention relates to a DC-SQUID measurement device that measures voltage characteristics.
本発明は、ＤＣ−３ＱＵ Ｉ Ｄの電流−電圧特性又は
磁束−電圧特性を測定するＤＣ−３ＱＵ Ｉ Ｄ測定装
置において、電流又は磁束のモニター出力と、電圧のモ
ニター出力との間で生しる位相差をＤＣ−ＳＱＵＩＤと
発振回路の間に、電圧モニター出力をフィードバック信
号として取り入れる移相回路を設けることにより、常に
零にするようにしたものである。The present invention provides a DC-3QUID measuring device for measuring current-voltage characteristics or magnetic flux-voltage characteristics of a DC-3QUID, in which a signal is generated between a current or magnetic flux monitor output and a voltage monitor output. The phase difference is always made zero by providing a phase shift circuit that takes in the voltage monitor output as a feedback signal between the DC-SQUID and the oscillation circuit.
従来は、第２図に示すような構成であった。 Conventionally, the configuration was as shown in FIG.
発振回路１の出力を、Ｖ／Ｉ変換回路５で電流に変換し
、ＤＣ−ＳＱＵＩＤ６に入力し、その時のＤＣ−ＳＱＵ
ＩＤ６の両端の電位差を、差動アンプ８で検出し、フィ
ルタ９で雑音を除去し出力していた。そして、このフィ
ルタ９の出力をモニターする第２の出力端子１１と発振
回路ｌの出力をモニターする第１の出力端子１０を、そ
れぞれオシロスコープに接続し、その波形をＸＹ表示さ
せることにより、Ｄ Ｃ−３Ｑ Ｕ Ｉ Ｄ ６の電流
−電圧特性又は磁束−電圧特性を測定していた。The output of the oscillation circuit 1 is converted into a current by the V/I conversion circuit 5 and inputted to the DC-SQUID 6, and the current DC-SQU
A differential amplifier 8 detects the potential difference between both ends of the ID 6, noise is removed by a filter 9, and the result is output. The second output terminal 11 that monitors the output of the filter 9 and the first output terminal 10 that monitors the output of the oscillation circuit 1 are connected to an oscilloscope, and the waveforms are displayed in XY. -3Q UID 6 current-voltage characteristics or magnetic flux-voltage characteristics were being measured.
従来のような構成によると、フィルタ９の影響により、
第１の出力端子１０の信号と、第２の出力端子１１の信
号との間に位相差が生じ、これを小さくすると雑音が十
分に除去できな（なってしまうという問題点があった。According to the conventional configuration, due to the influence of the filter 9,
There is a problem that a phase difference occurs between the signal at the first output terminal 10 and the signal at the second output terminal 11, and if this is made small, noise cannot be sufficiently removed.
〔課題を解決するための手段］
本発明は、これらの問題点を解決するために、フィルタ
９の出力をフィードバック信号として取り入れ、発振回
路１の出力の位相差が零になるように、発振回路１の出
力の位相を移す、移相手段２を発振回路１とＶ／Ｉ変換
回路５の間に設けたことを特徴とする。[Means for Solving the Problems] In order to solve these problems, the present invention incorporates the output of the filter 9 as a feedback signal, and adjusts the oscillation circuit so that the phase difference between the outputs of the oscillation circuit 1 becomes zero. The present invention is characterized in that a phase shifting means 2 is provided between the oscillation circuit 1 and the V/I conversion circuit 5, which shifts the phase of the output of the oscillation circuit 1.
前記のような構成によれば、フィルタ９の雑音の減衰率
を大きくしても、そのために生じる発振回路１の出力と
フィルタ９の出力との間の位相差は、移相手段によって
補正され、常に零となるので、位相差がなく、雑音も十
分に除去された電流電圧特性と磁束−電圧特性が測定で
きるようになる。According to the above configuration, even if the noise attenuation rate of the filter 9 is increased, the phase difference between the output of the oscillation circuit 1 and the output of the filter 9 that occurs due to this is corrected by the phase shifting means, Since it is always zero, it becomes possible to measure current-voltage characteristics and magnetic flux-voltage characteristics with no phase difference and noise sufficiently removed.
次に本発明の実施例を、図面に従って説明する。 Next, embodiments of the present invention will be described with reference to the drawings.
第１図は本発明の実施例であって、ｌは発振回路で、そ
の出力は第１の出力端子１０と、移相手段２に接続され
ている。移相手段２は、位相差検出回路３と移相回路４
とで構成されている。移相手段２はＶ／Ｉ変換回路５に
接続し、Ｖ／Ｉ変換回路５の出力はＤＣ−ＳＱＵＩＤ６
に入力し、その出力電圧を検出回路７で検出し、その出
力は第２の出力端子１１と移相手段２の位相差検出回路
３に接続している。検出回路７は、差動アンプ８にフィ
ルタ９とで構成されている。FIG. 1 shows an embodiment of the present invention, where l is an oscillation circuit whose output is connected to a first output terminal 10 and a phase shifting means 2. In FIG. The phase shift means 2 includes a phase difference detection circuit 3 and a phase shift circuit 4.
It is made up of. The phase shifting means 2 is connected to the V/I conversion circuit 5, and the output of the V/I conversion circuit 5 is connected to the DC-SQUID 6.
and its output voltage is detected by the detection circuit 7, and its output is connected to the second output terminal 11 and the phase difference detection circuit 3 of the phase shift means 2. The detection circuit 7 includes a differential amplifier 8 and a filter 9.
次に動作を説明する。Next, the operation will be explained.
発振回路１の出ツノと、フィルタ９の出力との間の位相
差が零の場合、発振回路１の出力は、移相手段２を通り
、Ｖ／Ｉ変換回路５で電流に変換され、ＤＣ−ＳＱＵＩ
Ｄ６に人力し、その時のジョセフソン素子の両端の電位
差を、差動７ンブ８で検出し、フィルタ９で雑音を除去
し出力する。このフィルタ９の出力をモニターする第２
の出力端子１１と、前記発振回路の出力をモニターする
第１の端子１０とを、例えばオシロスコープのＸＹモー
ドで測定することによってＤＣ−ＳＱＵＩＤ６の電流−
電圧特性又は磁束−電圧特性の測定が行える。When the phase difference between the output of the oscillation circuit 1 and the output of the filter 9 is zero, the output of the oscillation circuit 1 passes through the phase shifting means 2, is converted into a current by the V/I conversion circuit 5, and is converted into a DC current. -SQUI
A voltage difference between both ends of the Josephson element at that time is detected by a differential amplifier 8, noise is removed by a filter 9, and the result is output. A second filter that monitors the output of this filter 9
By measuring the output terminal 11 of the DC-SQUID 6 and the first terminal 10 for monitoring the output of the oscillator circuit, for example, in the XY mode of an oscilloscope, the current of the DC-SQUID 6 -
Voltage characteristics or magnetic flux-voltage characteristics can be measured.
発振回路１の出力と、フィルタ９の出力との間に位相差
が生じた場合、発振回路１の出力と、フィルタ９の出力
とから、位相差検出回路３によって、位相差が検出され
、位相差に相当する位相差信号が移相回路４に入力され
る。移相回路４は、この位相差信号に従い、発振回路１
の出力とフィルタ９の出力の位相差が零となるように、
発振回路１からの出力信号の位相をずらして、Ｖ／Ｉ変
換回路５に出力する。これによって、再び発振回路１の
出力と、フィルタ９の出力との位相差は零となり、前述
と同様にＤＣ−ＳＱＵＩＤ６の電流電圧特性、磁束−電
圧特性の測定が行える。When a phase difference occurs between the output of the oscillation circuit 1 and the output of the filter 9, the phase difference is detected by the phase difference detection circuit 3 from the output of the oscillation circuit 1 and the output of the filter 9. A phase difference signal corresponding to the phase difference is input to the phase shift circuit 4. According to this phase difference signal, the phase shift circuit 4 converts the oscillation circuit 1 into
So that the phase difference between the output of the filter 9 and the output of the filter 9 is zero,
The phase of the output signal from the oscillation circuit 1 is shifted and outputted to the V/I conversion circuit 5. As a result, the phase difference between the output of the oscillation circuit 1 and the output of the filter 9 becomes zero again, and the current-voltage characteristics and magnetic flux-voltage characteristics of the DC-SQUID 6 can be measured in the same manner as described above.
本発明は、ＤＣ−５ＱＵＩＤ以外にも、ジョセフソン素
子を使用した回路の電流−電圧特性又は磁束−電圧特性
の測定も可能である。In addition to the DC-5QUID, the present invention is also capable of measuring current-voltage characteristics or magnetic flux-voltage characteristics of a circuit using a Josephson element.
以上説明したように、本発明の構成を用いれば、フィル
タ９で十分に雑音を除去しても、その時発生する位相差
は、常に零となるように自動的に補正されるので、常に
低雑音で位相差のない測定ができる。As explained above, if the configuration of the present invention is used, even if the noise is sufficiently removed by the filter 9, the phase difference generated at that time is automatically corrected to always be zero, so that the noise is always low. Measurement without phase difference is possible.
さらに、フィルタ９の時定数の変動やその他の外乱によ
って、フィルタ９の出力と発振回路１の出力との間の位
相差の量に変動があったとしても、常に位相差は零に保
たれるという利点がある。Furthermore, even if the amount of phase difference between the output of filter 9 and the output of oscillation circuit 1 changes due to fluctuations in the time constant of filter 9 or other disturbances, the phase difference is always maintained at zero. There is an advantage.
第１図は本発明の実施例を示す構成図、第２図は従来例
を示す構成図である。
１・・・発振回路
２・・・移相手段
・位相差検出回路
・移相回路
・Ｖ／Ｉ変換回路
・ＤＣ−ＳＱＵＩＤ
・検出回路
・差動アンプ
・フィルタ
・第１の出力端子
・第２の出力端子
以上FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. 1... Oscillation circuit 2... Phase shifting means, phase difference detection circuit, phase shifting circuit, V/I conversion circuit, DC-SQUID, detection circuit, differential amplifier, filter, first output terminal, second output terminal or more
Claims (1)
出力端子と、この発振回路の信号を入力するＤＣ−ＳＱ
ＵＩＤと、このＤＣ−ＳＱＵＩＤの出力電圧を検出する
検出回路と、この検出回路の出力信号をモニターする第
２の出力端子とからなり、前記発振回路と前記第１の出
力端子との間に、前記検出回路の出力信号をフィードバ
ック信号としている移相手段が設けられていることを特
徴とするＤＣ−ＳＱＵＩＤ測定装置。An oscillation circuit, a first output terminal for monitoring the signal of this oscillation circuit, and a DC-SQ for inputting the signal of this oscillation circuit.
consisting of a UID, a detection circuit that detects the output voltage of this DC-SQUID, and a second output terminal that monitors the output signal of this detection circuit, and between the oscillation circuit and the first output terminal, A DC-SQUID measuring device characterized in that it is provided with phase shifting means that uses the output signal of the detection circuit as a feedback signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2098340A JPH03295471A (en) | 1990-04-13 | 1990-04-13 | Dc-squid measuring instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2098340A JPH03295471A (en) | 1990-04-13 | 1990-04-13 | Dc-squid measuring instrument |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03295471A true JPH03295471A (en) | 1991-12-26 |
Family
ID=14217175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2098340A Pending JPH03295471A (en) | 1990-04-13 | 1990-04-13 | Dc-squid measuring instrument |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03295471A (en) |
-
1990
- 1990-04-13 JP JP2098340A patent/JPH03295471A/en active Pending
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