CN110794908A - Voltage source for bias superconducting nanowire single-photon detector - Google Patents
Voltage source for bias superconducting nanowire single-photon detector Download PDFInfo
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- CN110794908A CN110794908A CN201910960084.6A CN201910960084A CN110794908A CN 110794908 A CN110794908 A CN 110794908A CN 201910960084 A CN201910960084 A CN 201910960084A CN 110794908 A CN110794908 A CN 110794908A
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- 239000002070 nanowire Substances 0.000 title claims abstract description 38
- 239000003990 capacitor Substances 0.000 claims abstract description 15
- 239000003381 stabilizer Substances 0.000 claims abstract description 10
- 238000012360 testing method Methods 0.000 claims description 23
- 238000001914 filtration Methods 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 10
- 238000001514 detection method Methods 0.000 description 7
- 238000013461 design Methods 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005693 optoelectronics Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
- G05F1/10—Regulating voltage or current
- G05F1/46—Regulating voltage or current wherein the variable actually regulated by the final control device is dc
- G05F1/56—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices
- G05F1/561—Voltage to current converters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/44—Electric circuits
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0084—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring voltage only
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/44—Electric circuits
- G01J2001/4413—Type
- G01J2001/442—Single-photon detection or photon counting
Abstract
The invention discloses a voltage source for a bias superconducting nanowire single photon detector, which adopts 220V alternating current voltage input to be changed into low-voltage alternating current input through a transformer, a diode, a capacitor, a voltage stabilizer and a fixed resistor are used for constructing a low-noise constant current source, and an adjustable resistor is connected with the constant current source in series, so that low-noise direct current voltage which can be linearly adjusted from 0V can be output at two ends of the adjustable resistor. The superconducting nanowire single-photon detector outputs stable direct-current voltage and is linearly adjustable from zero, and the voltage source can be used as a bias power supply of the superconducting nanowire single-photon detector.
Description
Technical Field
The invention relates to the field of optoelectronic devices, in particular to a voltage source for a bias superconducting nanowire single photon detector.
Background
The superconducting nanowire single photon detector has the characteristics of high detection efficiency, high counting rate, small dark counting rate, small time domain jitter, wide response spectrum and the like, and is a detector with excellent performance. The superconducting nanowire is partially converted into a resistive state from a superconducting state under single photon excitation, an optical signal is converted into a voltage signal, the voltage signal is read out by a reading circuit, and photon counting is further realized through counting of the voltage signal.
The performance of the superconducting nanowire single-photon detector is influenced by a bias voltage source, and the bias superconducting nanowire single-photon detector has the following characteristics as far as possible: the noise of the voltage source is small, i.e. the output voltage is a stable dc voltage. If the voltage source noise is large, i.e. the voltage jitter is large, large time domain jitter may be caused, and the time resolution of the detector is reduced. To fully detect and exert the performance of the detector, the time domain jitter of the detector is required to be as small as possible, so that a low-noise voltage source, namely a voltage source for biasing the superconducting nanowire single-photon detector, is required to meet the following requirements: the output is a dc voltage and is as stable as possible. And for convenient adjustment, the output voltage of the voltage source needs to be linearly adjustable from zero.
The existing voltage sources available in the market for biasing the superconducting nanowire single-photon detectors are generally expensive and complex in structure, so that the detection cost of the superconducting nanowire single-photon detectors is improved, and the application of the superconducting nanowire single-photon detectors is limited to a certain extent.
Therefore, the development of a voltage source for the bias superconducting nanowire single-photon detector with the characteristics of low manufacturing cost, zero adjustability, linearity adjustability and the like has important significance.
Disclosure of Invention
The invention provides a voltage source for biasing a superconducting nanowire single-photon detector, which outputs stable direct-current voltage and is linearly adjustable from zero, can be used as a test power source of the superconducting nanowire single-photon detector, and is described in detail as follows:
a voltage source for biasing a superconducting nanowire single photon detector adopts 220V alternating current voltage input, the alternating current input is changed into low voltage through a transformer, a diode, a capacitor, a voltage stabilizer and a fixed resistor form a low-noise constant current source, and an adjustable resistor is connected with the constant current source in series;
and a low-noise direct-current voltage which is linearly adjustable from 0V is output at two ends of the adjustable resistor.
Wherein, the output voltage end is connected with a micro-farad capacitor in parallel for secondary filtering.
Furthermore, the voltage stabilizer adopts a three-terminal adjustable voltage stabilizer; the adjustable resistor adopts a potentiometer.
Wherein the voltage source further comprises:
and designing and processing a shielding box, connecting the assembled voltage source in series with a resistor to form a low-noise current source which can be used as a bias current source to be connected into a superconducting nanowire single-photon detector circuit.
Furthermore, a threaded hole is formed in the bottom of the shielding box and used for fixing the circuit board and the transformer;
the front of the shielding box is provided with holes for fixing the output port and the potentiometer knob, and the rear of the shielding box is provided with square holes for fixing the three-terminal switch and the alternating voltage input port.
Wherein the test circuit comprises: the method comprises the steps of testing the output voltage of a voltage source and testing the output pulse of the superconducting nanowire single photon detector.
The output voltage test specifically comprises the following steps:
and adjusting the resistance value of the adjustable resistor, and testing the output voltage by using a direct-current voltage end of the universal meter.
The technical scheme provided by the invention has the beneficial effects that:
1. the voltage source designed by the invention has low noise required by the superconducting nanowire single-photon detector, and can achieve direct current voltage-stabilized output of any range by adjusting parameters of components, thereby being convenient for detection requirements under different conditions;
2. the voltage source has simple structure and low manufacturing cost, reduces the detection cost of the superconducting nanowire single-photon detector, and widens the application range of the superconducting nanowire single-photon detector to a certain extent.
Drawings
FIG. 1 is a circuit diagram of a regulated low noise voltage source;
the transformer part can select corresponding specifications according to the range requirement of output direct-current voltage, the low-voltage alternating-current voltage output by the transformer is rectified by a diode, a large capacitor and a small capacitor are connected in parallel and filtered, constant-current output is formed by a three-terminal adjustable voltage stabilizer, and after the low-voltage alternating-current voltage is filtered again by a small capacitor, an adjustable resistor is connected in series, so that the output adjustable direct-current voltage output can be realized.
FIG. 2 is a schematic diagram of a voltage-stabilized low-noise voltage source circuit with an output voltage of 0-12V;
FIG. 3 is a diagram illustrating simulation results of the relationship between the output voltage and the resistance of the adjustable resistor;
FIG. 4 is a simplified schematic diagram of a voltage source shielding box for voltage regulation and low noise;
wherein, the marked size is the size adopted by the built 0-12V linear output low-noise voltage source.
FIG. 5 is a diagram of a built and assembled 0-12V linearly adjustable voltage-stabilizing low-noise voltage source;
FIG. 6 is a graph showing the relationship between the output voltage of the built voltage source and the resistance of the adjustable resistor;
FIG. 7 is a flow chart of a low noise voltage source used in a superconducting nanowire single photon detector testing process;
the pulse laser used in the experiment is a passive mode-locked fiber laser. The optical pulse is divided into two beams by a beam splitter, one beam is converted into an electric signal by a photoelectric detector with small time domain jitter, and the electric signal enters a counter/oscilloscope channel 1; and the other beam passes through the polarization controller, is attenuated by the tunable attenuator and then enters the superconducting nanowire single-photon detector. The electric pulse signal output by the device is amplified by a two-stage low-noise radio frequency amplifier and input into an oscilloscope channel 2.
FIG. 8 is a time domain pulse image of a superconducting nanowire single photon detector under test (using the voltage source case of FIG. 5).
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below.
Example 1
The general technical scheme of the invention is as follows: a low-noise voltage output circuit capable of generating adjustable voltage is built on a small circuit board, a shielding box is designed and processed, a voltage source is assembled, an assembled low-noise voltage source is connected with a resistor with a certain resistance value in series to form a low-noise current source, the low-noise current source is connected into a testing circuit of the superconducting nanowire single-photon detector as an input end, and whether the superconducting nanowire single-photon detector can work normally or not is observed.
The first technical scheme is the design and construction of a low-noise voltage source circuit. The circuit design diagram is shown in fig. 1, the whole voltage source adopts 220V alternating current voltage input, is provided with a switch to control on-off, converts the input into low-voltage alternating current input through a transformer, uses a diode, a capacitor, a voltage stabilizer and a fixed resistor to form a low-noise constant current source, is connected with an adjustable resistor in series so as to output low-noise direct current voltage which is adjustable from 0V and is adjustable linearly at two ends of the adjustable resistor, and the circuit simulation result of the designed circuit is shown in fig. 2. The transformer adopts low power, such as 3W, 5W and the like, and the output end can select 12V, 15V, 18V and other alternating current output; the diodes can adopt 1N4001, 1N4002 … 1N4007 and the like, the capacitors are generally connected in parallel by a small capacitor with a microfarad magnitude and a large capacitor with a magnitude more than 1000 magnitude larger than the small capacitor, so as to play a role in filtering, and meanwhile, the output voltage end is also connected in parallel with a small capacitor with a microfarad magnitude for filtering again, so that the output voltage is more stable.
The voltage stabilizer adopts three-terminal adjustable voltage stabilizers such as LM317, LM217, LM117 and the like. The adjustable resistor is convenient to adjust, generally adopts a potentiometer, has random number of turns, and is generally more and better. The invention provides an example of a low-noise voltage stabilizing source for linearly outputting 0-12V direct-current voltage, a circuit schematic diagram is shown in figure 3, a 3W/15V parameter transformer is selected, the sizes of three capacitors are respectively 0.1 muF, 1000 muF and 0.01 muF, the resistance value of a fixed resistor is 100 omega, an adjustable resistor selects a 1k omega ten-turn potentiometer provided with a standard knob, and a three-terminal adjustable voltage stabilizer selects the model of LM 317.
The second technical scheme is the processing and assembling of the shielding box. The shielding box can be made of a common aluminum shielding box or other materials, the size of the device, namely the occupied space, is considered, the design condition of the shielding box is shown in fig. 4, and the specific size condition is determined according to the size of the transformer, the circuit board and other components. The bottom of the shielding box needs to be provided with a threaded hole for fixing the circuit board and the transformer, the specific size of the hole is determined according to the sizes of the used circuit board and the through hole of the transformer, and the threaded hole is generally an M3 size threaded hole; the front and back sides of the shielding box also need to be correspondingly perforated, one side needs to be provided with a circular hole for fixing the output port and the potentiometer knob, and the other side needs to be provided with a square hole for fixing the three-terminal switch and the alternating-current voltage input port. After the shielding box is processed, the whole voltage source is assembled into the shielding box, and the assembled simple low-noise voltage source object diagram is shown in fig. 5.
The third technical scheme is a testing part which comprises two parts, namely a designed voltage source finished product output voltage test and a designed voltage source bias superconducting nanowire single photon detector output pulse test. The first test is to adjust the resistance of the adjustable resistor and test the output voltage by using the direct-current voltage end of the multimeter, and the test result is shown in fig. 6. The second test is that the assembled voltage source is connected into the test circuit of the superconducting nanowire single photon detector, the detection parameters such as time domain jitter, dark count, system detection efficiency, device detection efficiency and the like are measured, and compared with the measured result of the existing high-price low-noise voltage source, the measured result is used as a basis for judging whether the designed voltage source is usable or not, the test circuit is shown in fig. 7, and the measured pulse curve is shown in fig. 8.
Example 2
The first implementation mode comprises the following steps: connecting circuit components
According to the circuit diagram shown in fig. 1, parts of components are welded on the circuit board, and the components on the circuit board are connected by copper wires according to the circuit diagram, wherein the adjustable resistor selects a potentiometer with a knob and is connected to the outside of the circuit board by the copper wires.
And connecting the welded circuit board with an alternating voltage power supply interface, a switch, a transformer and an output port.
The second embodiment: processing shielding box and assembling voltage source
The method comprises the steps of firstly measuring the sizes of a used circuit board, a transformer, a switch, an output port, an alternating voltage power supply interface and the like, selecting a shielding box with a proper size, drilling and the like, assembling the circuit board and the transformer assembled in an implementation mode in the shielding box, fixing the circuit board and the transformer by screws, and installing the output port, the switch, a potentiometer adjusting knob and the alternating voltage power supply interface on a shielding shell.
In the embodiment of the present invention, except for the specific description of the model of each device, the model of other devices is not limited, as long as the device can perform the above functions.
Those skilled in the art will appreciate that the drawings are only schematic illustrations of preferred embodiments, and the above-described embodiments of the present invention are merely provided for description and do not represent the merits of the embodiments.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (7)
1. A voltage source for biasing a superconducting nanowire single photon detector is characterized in that,
the voltage source adopts 220V alternating current voltage input and is changed into low-voltage alternating current input through a transformer, a low-noise constant current source is formed by a diode, a capacitor, a voltage stabilizer and a fixed resistor, and an adjustable resistor is connected with the constant current source in series;
and a low-noise direct-current voltage which is linearly adjustable from 0V is output at two ends of the adjustable resistor.
2. The voltage source of claim 1, wherein a microfarad capacitor is connected in parallel to the output voltage terminal for re-filtering.
3. The voltage source for biasing a superconducting nanowire single photon detector as claimed in claim 1, wherein said potentiostat is a three-terminal adjustable potentiostat; the adjustable resistor adopts a potentiometer.
4. The voltage source for biasing a superconducting nanowire single photon detector of claim 1, further comprising:
and designing and processing a shielding box, connecting the assembled voltage source in series with a resistor to form a low-noise current source which can be used as a bias current source to be connected into a superconducting nanowire single-photon detector circuit.
5. The voltage source for biasing a superconducting nanowire single photon detector as claimed in claim 4, wherein the bottom of the shielding box is provided with a threaded hole for fixing the circuit board and the transformer;
the front of the shielding box is provided with holes for fixing the output port and the potentiometer knob, and the rear of the shielding box is provided with square holes for fixing the three-terminal switch and the alternating voltage input port.
6. The voltage source for biasing superconducting nanowire single photon detectors of claim 4, wherein the test circuit comprises: the method comprises the steps of testing the output voltage of a voltage source and testing the output pulse of the superconducting nanowire single photon detector.
7. The voltage source for biasing a superconducting nanowire single photon detector as claimed in claim 6, wherein the output voltage test is specifically:
and adjusting the resistance value of the adjustable resistor, and testing the output voltage by using a direct-current voltage end of the universal meter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910960084.6A CN110794908A (en) | 2019-10-10 | 2019-10-10 | Voltage source for bias superconducting nanowire single-photon detector |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910960084.6A CN110794908A (en) | 2019-10-10 | 2019-10-10 | Voltage source for bias superconducting nanowire single-photon detector |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201479023U (en) * | 2009-08-24 | 2010-05-19 | 苏州海兹思纳米科技有限公司 | High-precision large-range positive-negative power supply |
| CN201830159U (en) * | 2010-10-11 | 2011-05-11 | 徐青春 | Adjustable direct current stabilized power supply |
| CN203522560U (en) * | 2013-11-05 | 2014-04-02 | 四川宝英光电有限公司 | Stabilized voltage supply circuit of rotary drum vacuum filter for sludge treatment |
| CN203933392U (en) * | 2014-04-17 | 2014-11-05 | 深圳怡化电脑股份有限公司 | A kind of D.C. regulated power supply |
| CN104242687A (en) * | 2014-07-31 | 2014-12-24 | 苏州华徕光电仪器有限公司 | Adjustable voltage-stabilizing power supply circuit |
| CN104320008A (en) * | 2014-11-07 | 2015-01-28 | 成都爱斯顿测控技术有限公司 | Adjustable direct current stabilized power supply circuit |
| CN204334358U (en) * | 2015-01-19 | 2015-05-13 | 成都联宇创新科技有限公司 | A kind of interface power supply circuit being applicable to computer |
| CN105226970A (en) * | 2015-10-28 | 2016-01-06 | 航天长峰朝阳电源有限公司 | The D.C. regulated power supply that output polarity is changed automatically |
| CN105262350A (en) * | 2015-10-27 | 2016-01-20 | 深圳市振邦智能科技有限公司 | Simple power supply circuit and test power supply |
| CN207304402U (en) * | 2017-10-26 | 2018-05-01 | 湖北广兴通信科技有限公司 | A kind of large power high efficiency AC power source converting apparatus |
-
2019
- 2019-10-10 CN CN201910960084.6A patent/CN110794908A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201479023U (en) * | 2009-08-24 | 2010-05-19 | 苏州海兹思纳米科技有限公司 | High-precision large-range positive-negative power supply |
| CN201830159U (en) * | 2010-10-11 | 2011-05-11 | 徐青春 | Adjustable direct current stabilized power supply |
| CN203522560U (en) * | 2013-11-05 | 2014-04-02 | 四川宝英光电有限公司 | Stabilized voltage supply circuit of rotary drum vacuum filter for sludge treatment |
| CN203933392U (en) * | 2014-04-17 | 2014-11-05 | 深圳怡化电脑股份有限公司 | A kind of D.C. regulated power supply |
| CN104242687A (en) * | 2014-07-31 | 2014-12-24 | 苏州华徕光电仪器有限公司 | Adjustable voltage-stabilizing power supply circuit |
| CN104320008A (en) * | 2014-11-07 | 2015-01-28 | 成都爱斯顿测控技术有限公司 | Adjustable direct current stabilized power supply circuit |
| CN204334358U (en) * | 2015-01-19 | 2015-05-13 | 成都联宇创新科技有限公司 | A kind of interface power supply circuit being applicable to computer |
| CN105262350A (en) * | 2015-10-27 | 2016-01-20 | 深圳市振邦智能科技有限公司 | Simple power supply circuit and test power supply |
| CN105226970A (en) * | 2015-10-28 | 2016-01-06 | 航天长峰朝阳电源有限公司 | The D.C. regulated power supply that output polarity is changed automatically |
| CN207304402U (en) * | 2017-10-26 | 2018-05-01 | 湖北广兴通信科技有限公司 | A kind of large power high efficiency AC power source converting apparatus |
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