Refraction type pulse radiation detector and method for generating high-amplitude signal thereof

Abstract

The invention discloses a refractive pulse radiation detector and a method for generating a high-amplitude signal by the refractive pulse radiation detector, and solves the technical problem that the existing refractive pulse radiation detector is difficult to realize high intrinsic resolution and improve the amplitude of an optical signal at the same time. Comprising an n-channel laser emitting n paths of probe light and further comprises n sensor structures, n delay regulators, an optical fiber beam combiner and a photoelectric detector, the input ends of the n sensor structures are connected with the output end of the n-channel laser through optical fibers, and the n sensor structures are used for converting the n paths of probe light into n beams of interference light and disturbing the interference light; the n delay regulators are respectively connected with the n sensor structures, and the input end of the optical fiber beam combiner is connected with the output ends of the n delay regulators through optical fibers; the photoelectric detector is connected with the output end of the optical fiber combiner. By means of an interference signal superposition mode, high intrinsic time resolution is kept, and meanwhile the amplitude response of the refraction type pulse radiation detector is improved.

Description

Technical Field

[0001] The invention relates to a pulse radiation detector and an optimization method thereof, and in particular to a refractory pulse radiation detector and a method for generating a high-amplitude signal thereof. Background Art

[0002] High-energy pulsed beams such as short X / γ-ray beams or electron beams generated by advanced scientific devices have strong penetrating power and last only tens of picoseconds. The pulse time waveform can be used to monitor the working status of advanced scientific devices and provide a reference for scientific experiments. Short electron beams can be measured based on technologies such as transition radiation, electro-optical effect, and space-time conversion. Due to the low energy deposition efficiency and electrical neutrality, it is difficult to measure high-energy short X / γ-ray beams, which exceeds the time resolution capability of most X / γ-ray detectors and is challenging.

[0003] The intrinsic time resolution of the refractometric pulse radiation detector is only related to the time length of the process of excess carrier generation by the ray photons. According to theoretical calculations, when a delta ray pulse is incident, the time length of the process of excess carrier generation is mainly determined by the material thickness. The intrinsic time resolution of a thin material with a thickness of 300 microns can reach 3.3 picoseconds. Therefore, the refractometric pulse radiation detector using thin materials has a high intrinsic time resolution and is a competitive solution for measuring the time behavior of ultrashort X / γ-ray beams.

[0004] The disadvantage of using thin material refractometric pulse radiation detectors is that they have low sensitivity. It is difficult to achieve effective signal output with only a 300-micron thick material. Although using a thicker material can improve the detector sensitivity, the intrinsic time resolution will also deteriorate. The intrinsic time resolution of a 10mm thick material is 33 picoseconds, which cannot achieve the measurement purpose. Summary of the invention

[0005] The purpose of the present invention is to solve the technical problem that it is difficult to simultaneously achieve high intrinsic resolution and high signal amplitude in a refractory pulse radiation detector using thin materials, and to provide a refractory pulse radiation detector and a method for generating a high-amplitude signal thereof.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A refractometric pulse radiation detector comprises an n-channel laser, wherein the n-channel laser is used to output n-path probe light; the detector is special in that it also comprises n sensor structures, n delay regulators, a fiber combiner, and a photoelectric detector, wherein n≥2;

[0008] The input ends of the n sensor structures are respectively connected to the output ends of the n-channel lasers through optical fibers, so as to convert the n-path probe lights into n-beam interference lights respectively. The n sensor structures are respectively provided with sensitive areas, so as to receive radiation pulses that disturb the interference lights.

[0009] The n delay regulators are respectively connected to the output ends of the n sensor structures, and are used to adjust the delay amount output by the corresponding sensor structure;

[0010] The input end of the optical fiber combiner is connected to the output ends of the n delay regulators through optical fibers, so as to couple the output results of the n delay regulators to obtain a combined light beam;

[0011] The photoelectric detector is connected to the output end of the optical fiber combiner and is used to detect the combined light output by the optical fiber combiner to obtain the time waveform of the radiation pulse to be measured, that is, the high amplitude signal.

[0012] Furthermore, each of the sensor structures includes a fiber circulator, a semiconductor chip, and a single-mode optical fiber a; the input end of the fiber circulator is connected to an output end of an n-channel laser through an optical fiber, the output end of the fiber circulator is connected to one end of the single-mode optical fiber a, and the other end of the single-mode optical fiber a is connected to the input end of a delay regulator;

[0013] One side of the semiconductor wafer is a sensitive area for receiving radiation pulses, and the other side is connected to the isolation end of the optical fiber circulator through an optical fiber.

[0014] Furthermore, the n-channel probe lights output by the n-channel laser are direct current, tunable, narrow-band near-infrared probe lights, and the wavelengths and powers of the n-channel probe lights can be adjusted individually.

[0015] Furthermore, the sensitive areas of the n semiconductor wafers are staggered with each other in the horizontal direction.

[0016] Furthermore, the maximum adjustment time of each delay regulator is greater than or equal to the maximum time difference between the signals generated by the n-channel sensor structure and the photodetector caused by the radiation pulse.

[0017] Furthermore, the optical fiber between the input end of the sensor structure and the output end of the n-channel laser is a single-mode optical fiber b.

[0018] Furthermore, the radiation pulse is a single X / γ-ray pulse.

[0019] A method for generating a high-amplitude signal from a refractory pulse radiation detector is characterized in that it comprises the following steps:

[0020] Step 1, adjusting the optical path lengths of n probe lights to be consistent through the optical fiber length, completing the coarse adjustment of the optical path length;

[0021] Step 2: Use near-infrared femtosecond or picosecond laser pulses as timing radiation pulses to respectively incident on the sensitive area of ​​each sensor structure, and record the time when each timing radiation pulse is received on the photodetector;

[0022] Step 3, adjusting the delay regulator respectively according to the time when each timing radiation pulse is received by the photoelectric detector, so that the time when each timing radiation pulse arrives at the photoelectric detector is consistent;

[0023] Step 4: Turn on the n-channel laser to output n-channel probe lights, and adjust the parameters of each channel of probe light, so that the probe lights interfere in the corresponding sensor structures to generate interference light;

[0024] Step 5. Place the sensitive areas of n sensor structures in an offset manner within the cross section of the radiation pulse to be measured. The radiation pulse to be measured disturbs the interference light within the n sensor structures respectively, and transmits the interference light to the fiber optic combiner for beam combining to obtain combined light. The combined light is incident on a photodetector to obtain a time waveform of the radiation pulse to be measured, that is, a high-amplitude signal.

[0025] Furthermore, in step 4, adjusting the parameters of each probe light specifically refers to adjusting the output intensity and wavelength of each probe light.

[0026] Beneficial effects of the present invention:

[0027] 1. The present invention provides a refractometric pulse radiation detector and a method for generating a high-amplitude signal thereof, which improves the amplitude response of the refractometric pulse radiation detector while maintaining a high intrinsic time resolution by means of interference signal superposition, thereby providing the possibility for the refractometric pulse radiation detector to realize ultrashort X / γ-ray pulse measurement.

[0028] 2. The present invention provides a refractory pulse radiation detector that can be used to measure and monitor the arrival time of ray pulses with high timing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of an embodiment of a refractory pulse radiation detector of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of a sensor in an embodiment of a refractory pulse radiation detector of the present invention.

[0031] In the figure, 1-n channel laser; 2-sensor structure, 201-fiber circulator, 202-semiconductor chip, 203-single mode optical fiber a; 3-delay regulator; 4-fiber combiner; 5-photoelectric detector. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] like Figure 1 As shown, this embodiment is a refractory pulse radiation detector, comprising an n-channel laser 1, n sensor structures 2, n delay regulators 3, a fiber combiner 4, and a photodetector 5, wherein n≥2;

[0034] In this embodiment, the n-channel laser 1 is used to output n-channel DC, tunable, narrow-band near-infrared probe lights, and the wavelengths and powers of the n-channel probe lights can be adjusted separately without affecting each other.

[0035] The n sensor structures 2 include an optical fiber circulator 201, a semiconductor chip 202, and a single-mode optical fiber a203; the input end of the optical fiber circulator 201 is connected to an output end of the n-channel laser 1 through a single-mode optical fiber b, the output end of the optical fiber circulator 201 is connected to one end of the single-mode optical fiber a203, and the other end of the single-mode optical fiber a203 is connected to the delay regulator 3, one side of the semiconductor chip 202 is a sensitive area for receiving radiation pulses (which can be a single near-infrared femtosecond or single picosecond laser pulse, or a short X / γ-ray beam or an electric sub-bundle), and the other side is connected to the isolation end of the optical fiber circulator 201 through an optical fiber; the single-mode optical fibers a203 of the n sensor structures 2 are connected to the input end of the optical fiber combiner 4 through a delay adjuster 3 respectively; the material type, thickness, and surface treatment of the optical fiber circulator 201, the semiconductor chip 202, and the single-mode optical fiber a203 in the n sensor structures 2 are consistent, and the working wavelength variation range between each structure is less than one cycle to minimize the impact of the wavelength difference of the refractive index response, and the detection area of ​​the structure is located at the center of the ray channel.

[0036] After the probe light output by the n-channel laser 1 enters the optical fiber circulator 201 through the input end and passes through the isolation end, a portion of the probe light is reflected by the surface of the semiconductor chip 202 and enters the optical fiber circulator 201, and the remaining portion is transmitted into the semiconductor chip 202, and enters the optical fiber circulator 201 after being reflected by the other side of the semiconductor chip 202. The reflected light and the transmitted light interfere with each other in the optical fiber circulator 201 to form interference light.

[0037] In this embodiment, the timing radiation pulse is a single near-infrared femtosecond or single picosecond laser pulse.

[0038] In this embodiment, the wavelength of the probe light is the same as the wavelength of the timing radiation pulse. The sensitive areas of the n semiconductor chips 202 are staggered in the horizontal direction and are evenly distributed in the cross-section of the radiation pulse. When the radiation pulse is emitted, it can enter the sensitive areas of different semiconductor chips 201.

[0039] In this embodiment, the single-mode optical fiber a203 is connected to the delay regulator 3; by applying different voltages, the optical signal delay of the optical fiber path can be adjusted within a certain range, the moment when the signal pulse enters the photodetector 5 can be controlled, and the signal light pulses of each path can be sent to the photodetector 5 at the same time, so that the signal light pulse intensities are superimposed.

[0040] In this embodiment, the input end of the fiber combiner 4 is connected to the output ends of n delay adjusters 3 through an optical fiber, so as to combine n delay-adjusted light beams to obtain combined light beams. The fiber combiner 4 uses a fiber combiner with high ray transmittance and low scattering, so that the rays have considerable intensity at the rear end and generate an effective superposition signal.

[0041] In this embodiment, the maximum adjustment time of each delay regulator 3 is greater than or equal to the maximum time difference between the signals generated by the n-channel sensor structure and the photoelectric detector caused by the radiation pulse to be measured.

[0042] In this embodiment, an n-channel laser 1, a sensor structure 2, and a delay adjuster 3 are used as an interference optical path component; an interference optical path can be generated, and a high-amplitude signal is synthesized in a fiber combiner 4 under the disturbance of a radiation pulse.

[0043] In this embodiment, the photodetector 5 is connected to the output end of the optical fiber combiner 4 and is used to detect the combined light output by the optical fiber combiner 4 to obtain the time waveform of the radiation pulse to be measured, that is, the high amplitude signal.

[0044] This embodiment also provides a method for generating a high-amplitude signal by a refractory pulse radiation detector, including two parts: coarse adjustment and fine adjustment; wherein, the coarse adjustment of each optical path is completed by controlling the optical path and the optical fiber length. The sensor structure 2 uses a fiber optic circulator 201, a semiconductor chip 202, and a single-mode optical fiber a203 of the same model. The speed at which the radiation pulse travels between the semiconductor chips of the sensor structure 2 is calculated according to the speed of light in the air. For a certain sensor structure 2, after the delay regulator is adjusted to a suitable delay value, the time for the disturbance signal generated by the radiation pulse to be transmitted from the rear surface of the semiconductor to the photodetector remains the same. Before the delay regulator is adjusted, the time difference of each path is not greater than the maximum adjustment range of the delay regulator 3.

[0045] The present embodiment provides a method for generating a high-amplitude signal by a refractory pulse radiation detector, specifically comprising the following steps:

[0046] Step 1, adjusting the optical path lengths of n probe lights to be consistent through the optical fiber length, completing the coarse adjustment of the optical path length;

[0047] Step 2: Use a near-infrared femtosecond or picosecond laser pulse as a timing laser pulse, and the cross section of the timing laser pulse can fully cover the sensitive areas of the n sensor structures 2. The wavelength of the timing laser pulse is equal to the wavelength of the probe light. The timing laser pulse enters the detector from the first sensor structure 2 and enters the sensitive area of ​​each sensor structure 2 respectively, and the time of receiving each timing radiation pulse on the photodetector 5 is recorded respectively.

[0048] In this embodiment, a single near-infrared femtosecond or single picosecond laser pulse is used to irradiate the sensitive area of ​​each sensing structure 2, so that high timing accuracy can be maintained. By adjusting the delay regulator 3 of each channel, the arrival time of each probe light is made to meet the expectation, and the delay adjustment is completed. This state is also maintained during normal testing.

[0049] Step 3, adjusting the delay regulator 3 according to the time when each timing radiation pulse is received by the photodetector 5, so that the time when each timing radiation pulse reaches the photodetector 5 is consistent;

[0050] Step 4, turning on the n-channel laser 1 to output n-channel probe lights, and adjusting the parameters of each channel of probe light, so that the probe lights interfere in the corresponding sensor structures 2 to generate interference light;

[0051] Step 5, the sensitive areas of the n sensor structures 2 are staggered and placed in the cross section of the radiation pulse to be measured. The radiation pulse to be measured disturbs the interference light in the n sensor structures 2 respectively, and transmits it to the optical fiber combiner 4 for combining to obtain combined light. The combined light is incident on the photodetector 5 to obtain the time waveform of the radiation pulse to be measured, that is, the high amplitude signal.

[0052] The present embodiment provides a refractometric pulse radiation detector and a method for generating a high-amplitude signal thereof, which can simultaneously have high intrinsic time resolution and high response, providing a solution for measuring ultrashort X / γ-ray pulses, and can also be used for measuring and monitoring the arrival time of ray pulses with high timing accuracy.

[0053] The above description is only a specific embodiment of the present invention, and a comparison of the effects of the specific embodiments and the related comparative examples, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A refractometric pulse radiation detector, comprising an n-channel laser (1), wherein the n-channel laser (1) is used to output n-channel probe light; characterized in that: It also includes n sensor structures (2), n delay regulators (3), an optical fiber combiner (4), and a photodetector (5), wherein n≥2; The input ends of the n sensor structures (2) are respectively connected to the output ends of the n-channel laser (1) through optical fibers, so as to convert the n-path probe lights into n-beam interference lights, and sensitive areas are respectively arranged on the n sensor structures (2) to receive radiation pulses that disturb the interference lights; The n delay regulators (3) are respectively connected to the output ends of the n sensor structures (2) and are used to adjust the delay amount output by the corresponding sensor structure (2); The input end of the optical fiber combiner (4) is connected to the output ends of the n delay adjusters (3) through optical fibers, so as to couple the output results of the n delay adjusters (3) to obtain combined light; The photoelectric detector (5) is connected to the output end of the optical fiber combiner (4) and is used to detect the combined light output by the optical fiber combiner (4) to obtain the time waveform of the radiation pulse to be measured, that is, the high amplitude signal.

2. The refractometric pulse radiation detector according to claim 1, characterized in that: Each of the sensor structures (2) comprises a fiber optic circulator (201), a semiconductor chip (202), and a single-mode optical fiber a (203); the input end of the fiber optic circulator (201) is connected to an output end of an n-channel laser (1) via an optical fiber, the output end of the fiber optic circulator (201) is connected to one end of the single-mode optical fiber a (203), and the other end of the single-mode optical fiber a (203) is connected to the input end of a delay adjuster (3); One side of the semiconductor chip (202) is a sensitive area for receiving radiation pulses, and the other side is connected to the isolation end of the optical fiber circulator (201) through an optical fiber.

3. The refractometric pulse radiation detector according to claim 1, characterized in that: The n-channel probe lights output by the n-channel laser (1) are direct current, tunable, narrow-band near-infrared probe lights, and the wavelengths and powers of the n-channel probe lights can be adjusted individually.

4. The refractometric pulse radiation detector according to claim 2, characterized in that: The sensitive areas of the n semiconductor wafers (202) are staggered in the horizontal direction.

5. The refractometric pulse radiation detector according to claim 1, characterized in that: The maximum adjustment time of each delay regulator (3) is greater than or equal to the maximum time difference between the signals generated by the n-channel sensor structure and the photoelectric detector caused by the radiation pulse.

6. The refractometric pulse radiation detector according to claim 1, characterized in that: The optical fiber between the input end of the sensor structure (2) and the output end of the n-channel laser (1) is a single-mode optical fiber b.

7. The refractometric pulse radiation detector according to claim 1, characterized in that: The radiation pulse is a single X / gamma ray pulse.

8. A method for generating a high-amplitude signal based on the refractory pulse radiation detector according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, adjusting the optical path lengths of n probe lights to be consistent through the optical fiber length, completing the coarse adjustment of the optical path length; Step 2: using near-infrared femtosecond or picosecond laser pulses as timing radiation pulses to respectively incident on the sensitive area of ​​each sensor structure (2), and respectively recording the time when each timing radiation pulse is received on the photodetector (5); Step 3, adjusting the delay regulator (3) in combination with the time when each timing radiation pulse is received by the photoelectric detector (5), so that the time when each timing radiation pulse arrives at the photoelectric detector (5) is consistent; Step 4, turning on the n-channel laser (1) to output n-channel probe lights, and adjusting the parameters of each channel of probe light, so that the probe lights interfere in the corresponding sensor structures (2) to generate interference light; Step 5, the sensitive areas of the n sensor structures (2) are staggered and placed in the cross section of the radiation pulse to be measured, the radiation pulse to be measured disturbs the interference light in the n sensor structures (2) respectively, and is transmitted to the optical fiber combiner (4) for beam combining to obtain combined light, and the combined light is incident on the photodetector (5) to obtain the time waveform of the radiation pulse to be measured, that is, the high amplitude signal.

9. The method for generating a high-amplitude signal by a refractometric pulse radiation detector according to claim 1, characterized in that: In step 4, adjusting the parameters of each probe light specifically refers to adjusting the output intensity and wavelength of each probe light.

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