Cathode fluorescence detection system and method based on superconducting nanowire single-photon detector

Abstract

The invention provides a cathode fluorescence detection system and method based on a superconducting nanowire single-photon detector, and relates to the technical field of cathode fluorescence detection.The system comprises a cathode fluorescence spectrum processing unit used for receiving a cathode fluorescence CL signal generated by an electron microscope, preprocessing the CL signal and sending the preprocessed CL signal to an electron microscope; transmitting the processed signal to a superconducting nanowire single-photon detector for detection; the superconducting nanowire single-photon detector is used for detecting the processed signal and inputting the generated detection signal into the data acquisition and processing unit for post-processing; and the data acquisition and processing unit is used for post-processing the received detection signal and generating a processing result. According to the cathode fluorescence detection system and method based on the superconducting nanowire single-photon detector, the superconducting nanowire single-photon detector is applied to cathode fluorescence detection, so that the detection sensitivity, waveband coverage and detection time resolution of cathode fluorescence are greatly improved.

Description

Technical Field

[0001] This application relates to the field of cathodoluminescence detection technology, and in particular to a cathodoluminescence detection system and method based on a superconducting nanowire single-photon detector. Background Technology

[0002] Cathodoluminescence (CL) is a characterization technique based on the excitation of light from materials by high-energy electron beams. It obtains imaging or spectroscopic results by collecting and detecting photon signals generated by the interaction of electrons with materials, structures and other samples, thereby revealing the electronic structure, optical properties and microscopic defects of the sample under test.

[0003] The key to cathodoluminescence detection technology lies in the accurate detection of cathodoluminescence signals. However, the cathodoluminescence detection schemes in related technologies are difficult to detect extremely low-power CL signals and mid-infrared CL signals. The detection sensitivity and the coverage of the bands cannot meet the needs of different scenarios. Summary of the Invention

[0004] The purpose of this application is to provide a cathodoluminescence detection system and method based on a superconducting nanowire single-photon detector. By applying the superconducting nanowire single-photon detector to cathodoluminescence detection, the detection sensitivity, band coverage and detection time resolution of cathodoluminescence are greatly improved.

[0005] This application provides a cathodoluminescence detection system based on a superconducting nanowire single-photon detector, comprising: The system comprises a cathodoluminescence (CFL) spectral processing unit, a superconducting nanowire single-photon detector, and a data acquisition and processing unit. The CFL spectral processing unit receives cathodoluminescence (CL) signals generated by an electron microscope, preprocesses the CL signals, and transmits the preprocessed CL signals to the superconducting nanowire single-photon detector. The superconducting nanowire single-photon detector detects the preprocessed CL signals and inputs the generated detection signal to the data acquisition and processing unit. The data acquisition and processing unit performs post-processing on the received detection signal to generate a processing result. The preprocessing includes at least one of the following: spectral modulation of the received CL signal and filtering of noise bands in the received CL signal. The post-processing includes any one of the following: cathodoluminescence detection, cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging.

[0006] Optionally, the cathode fluorescence spectroscopy processing unit includes: a Fourier transform spectrometer and a filtering system; the data acquisition and processing unit includes: a time-to-digital converter and a host computer.

[0007] Optionally, the cathodoluminescence spectroscopy processing unit is specifically used to perform spectral modulation on the received CL signal using a Fourier transform spectrometer when the post-processing is cathodoluminescence spectral detection or cathodoluminescence spectral imaging, and to filter the noise band in the spectrally modulated CL signal; the data acquisition and processing unit is specifically used to input the received detection signal and synchronization signal into the time-to-digital converter for recording, and input the recording result into the host computer for post-processing; wherein, the synchronization signal is output by the Fourier transform spectrometer; the synchronization signal is used to characterize the position of the interferometer moving mirror in the Fourier transform spectrometer.

[0008] Optionally, the cathodoluminescence spectral processing unit includes a filtering system; the data acquisition and processing unit includes a time-to-digital converter and a host computer.

[0009] Optionally, the data acquisition and processing unit includes: a time-to-digital converter and a host computer; the cathodoluminescence spectroscopy processing unit is specifically used to filter the noise band in the received CL signal when the post-processing is cathodoluminescence detection or cathodoluminescence imaging; the data acquisition and processing unit is specifically used to input the received detection signal into the time-to-digital converter for recording, and input the recording result into the host computer for post-processing.

[0010] This application also provides a cathodoluminescence detection method based on a superconducting nanowire single-photon detector, including: The system receives the detection signal sent by the superconducting nanowire single-photon detector and the measurement position information corresponding to the detection signal sent by the electron microscope; based on the measurement position information, it determines the current measurement position of the object under test, and based on the detection signal, it determines the intensity result of the CL signal associated with the current measurement position.

[0011] This application also provides a cathodoluminescence imaging method based on a superconducting nanowire single-photon detector, including: The system receives detection signals from the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signals from the electron microscope. Based on the received measurement position information, it determines the current measurement position of the object under test and determines the intensity of the CL signal associated with the current measurement position of the object under test based on the received detection signals, until the intensity of the CL signal associated with each measurement position of the object under test is obtained. Based on the intensity of the CL signal associated with each measurement position of the object under test, it performs image reconstruction to obtain the cathodoluminescence image of the object under test. The CL signals associated with different measurement positions of the object under test are obtained by changing the scanning position of the electron beam in the electron microscope.

[0012] This application also provides a cathodoluminescence spectroscopy detection method based on a superconducting nanowire single-photon detector, including: The system receives the detection signal sent by the superconducting nanowire single-photon detector and the synchronization signal sent by the Fourier transform spectrometer in the cathodoluminescence spectroscopy processing unit; based on the detection signal and the synchronization signal, it performs time-correlated single-photon counting to obtain the counting result, and calculates the cathodoluminescence spectrum based on the counting result.

[0013] This application also provides a cathodoluminescence spectroscopy imaging method based on a superconducting nanowire single-photon detector, including: The system receives detection signals from the superconducting nanowire single-photon detector, synchronization signals from the Fourier transform spectrometer in the cathodoluminescence spectroscopy processing unit, and measurement position information corresponding to the detection signals from the electron microscope. Based on the received measurement position information, the system determines the current measurement position of the object under test, and based on the received detection and synchronization signals, determines the single-photon count result associated with the current measurement position of the object under test, until the single-photon count result associated with each measurement position of the object under test is obtained. Based on the single-photon count result associated with each measurement position of the object under test, the system obtains the cathodoluminescence spectral image of the object under test. The single-photon count result is generated by time-correlated single-photon counting based on the detection and synchronization signals. The CL signals associated with different measurement positions of the object under test are obtained by changing the scanning position of the electron beam in the electron microscope.

[0014] This application also provides an electronic device having the above-mentioned cathodoluminescence detection system based on a superconducting nanowire single-photon detector, which is used to perform the steps of the above-mentioned cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method.

[0015] This application also provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the above-described cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method.

[0016] This application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the above-described cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method.

[0017] This application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method.

[0018] The cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application includes: a cathodoluminescence spectral processing unit, a superconducting nanowire single-photon detector, and a data acquisition and processing unit. The cathodoluminescence spectral processing unit receives cathodoluminescence (CL) signals generated by an electron microscope, preprocesses the CL signals, and transmits the processed CL signals to the superconducting nanowire single-photon detector for detection. The superconducting nanowire single-photon detector detects the processed CL signals and inputs the generated detection signals to the data acquisition and processing unit for post-processing. The data acquisition and processing unit performs post-processing on the received detection signals to generate processing results. The preprocessing includes at least one of the following: spectral modulation of the received CL signals and filtering of noise bands in the received CL signals. The post-processing includes any one of the following: cathodoluminescence detection, cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging. Thus, by applying a superconducting nanowire single-photon detector to cathodoluminescence detection, the detection sensitivity, band coverage, and detection time resolution of cathodoluminescence are greatly improved. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application; Figure 2 This is a schematic flowchart of the cathodoluminescence detection method based on a superconducting nanowire single-photon detector provided in this application; Figure 3 This is one of the flowcharts of the cathodoluminescence imaging method based on a superconducting nanowire single-photon detector provided in this application; Figure 4 This is the second schematic diagram of the cathodoluminescence imaging method based on a superconducting nanowire single-photon detector provided in this application; Figure 5This is one of the flowcharts of the cathodoluminescence spectroscopy detection method based on a superconducting nanowire single-photon detector provided in this application; Figure 6 This is the second schematic diagram of the cathodoluminescence spectroscopy detection method based on a superconducting nanowire single-photon detector provided in this application; Figure 7 This is one of the flowcharts of the cathodoluminescence spectroscopy imaging method based on a superconducting nanowire single-photon detector provided in this application; Figure 8 This is the second schematic diagram of the cathodoluminescence spectroscopy imaging method based on a superconducting nanowire single-photon detector provided in this application; Figure 9 This is a schematic diagram of the SPR signal intensity in different bands provided in this application; Figure 10 This is a schematic diagram of the structure of the electronic device provided in this application. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] The terms "first," "second," etc., used in this application's specification are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects have an "or" relationship.

[0023] Cathodoluminescence (CL) technology is typically based on scanning electron microscopy (SEM) or transmission electron microscopy (TEM), and is generally equipped with detectors such as photomultiplier tubes (PMT), charge-coupled devices (CCD), and complementary metal-oxide-semiconductor (CMOS), enabling the detection of cathodoluminescence signals in the ultraviolet, visible, and near-infrared bands. Superconducting nanowire single-photon detectors (SNSPDs) are an emerging single-photon detection technology. They are nanowires approximately 100 nm wide and 5–10 nm thick, commonly made of materials such as niobium nitride (NbN), titanium niobium nitride (NbTiN), and silicon tungsten (WSi). During operation, the SNSPD is cooled below the material's superconducting critical temperature and enters a superconducting state. After absorbing a photon, the SNSPD undergoes a transition between a superconducting and non-superconducting state and outputs a corresponding voltage pulse as the signal indicating the detection of the single photon. Compared to other detectors, the SNSPD has extremely high sensitivity, achieving a detection efficiency close to 100%, and reducing the dark count to below 10. -4 Hz; SNSPD can cover an ultra-wide wavelength range. In addition to the visible and near-infrared bands, SNSPD can also detect ultraviolet and mid-infrared. SNSPD can achieve extremely high detection speed, with a maximum count rate in the GHz range. SNSPD also has extremely high time accuracy, with the time jitter of the output electrical pulse as low as the ps range.

[0024] Based on the aforementioned characteristics of superconducting nanowire single-photon detectors, this application provides a cathodoluminescence detection system based on a superconducting nanowire single-photon detector, comprising a cathodoluminescence spectral processing unit, a superconducting nanowire single-photon detector, and a data acquisition and processing unit. The cathodoluminescence spectral processing unit receives cathodoluminescence (CL) signals generated by an electron microscope, preprocesses the CL signals, and transmits the preprocessed CL signals to the superconducting nanowire single-photon detector. The superconducting nanowire single-photon detector detects the preprocessed CL signals and inputs the generated detection signals to the data acquisition and processing unit. The data acquisition and processing unit performs post-processing on the received detection signals to generate processing results. The preprocessing includes at least one of the following: spectral modulation of the received CL signals and filtering of noise bands in the received CL signals. The post-processing includes any one of the following: cathodoluminescence detection, cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging.

[0025] For example, such as Figure 1 As shown, in the scanning electron microscope (SEM) subsystem, the electron gun emits electrons that are incident on the material / sample to be imaged (i.e., the object under test mentioned above). A magnetic lens controls the specific position of the electrons, and the resulting CL signal is collected in an optical fiber and sent to the CL spectral modulation and filtering system (i.e., the cathode fluorescence spectral processing unit mentioned above). In the CL spectral modulation and filtering subsystem, the CL signal first undergoes intensity modulation by the interferometer within the Fourier transform spectrometer (FTS). The modulation of different wavelengths is determined by the position of the moving mirror in the interferometer. After this, photons in the noise band of the signal are filtered out by the filtering system. Finally, the CL signal is sent to the SNSPD subsystem (i.e., the superconducting nanowire single-photon detector mentioned above) for detection.

[0026] In one possible implementation, if spectral detection is required, an FTS can be added to the cathodoluminescence spectral processing unit for spectral modulation.

[0027] Exemplarily, the cathodoluminescence spectroscopy processing unit includes a Fourier transform spectrometer and a filtering system; the data acquisition and processing unit includes a time-to-digital converter and a host computer. The cathodoluminescence spectroscopy processing unit is used to perform spectral modulation on the received CL signal using the Fourier transform spectrometer, and to filter noise bands in the spectrally modulated CL signal when the post-processing is cathodoluminescence spectral detection or cathodoluminescence spectral imaging; the data acquisition and processing unit specifically inputs the received detection signal and synchronization signal into the time-to-digital converter for recording, and inputs the recording results into the host computer for post-processing; wherein, the synchronization signal is output by the Fourier transform spectrometer; the synchronization signal is used to characterize the position of the interferometer moving mirror in the Fourier transform spectrometer.

[0028] like Figure 1 As shown, the single-photon detection signal generated by the SNSPD, along with the synchronization signal used in the Fourier Transform Spectrometer (FTS) to display the position of the moving mirror, is sent to a Time-to-Digital Converter (TDC) for recording. The recorded results are then sent to a host computer for further processing. In addition, the host computer is also responsible for acquiring and recording the control signals of the SEM and the synchronization signals of the FTS.

[0029] In another possible implementation, if spectral detection is not required, it can be achieved by adjusting the CL signal interference optical path in the FTS to a direct optical path, or by directly canceling the FTS.

[0030] For example, the cathodoluminescence spectral processing unit includes a filtering system; the data acquisition and processing unit includes a time-to-digital converter and a host computer. The data acquisition and processing unit includes a time-to-digital converter and a host computer; the cathodoluminescence spectral processing unit is used to filter noise bands in the received CL signal when the post-processing is cathodoluminescence detection or cathodoluminescence imaging; specifically, the data acquisition and processing unit is used to input the received detection signal into the time-to-digital converter for recording, and input the recording result into the host computer for post-processing.

[0031] The cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application includes: a cathodoluminescence spectral processing unit, a superconducting nanowire single-photon detector, and a data acquisition and processing unit. The cathodoluminescence spectral processing unit receives cathodoluminescence (CL) signals generated by an electron microscope, preprocesses the CL signals, and transmits the processed CL signals to the superconducting nanowire single-photon detector for detection. The superconducting nanowire single-photon detector detects the processed CL signals and inputs the generated detection signals to the data acquisition and processing unit for post-processing. The data acquisition and processing unit performs post-processing on the received detection signals to generate processing results. The preprocessing includes at least one of the following: spectral modulation of the received CL signals and filtering of noise bands in the received CL signals. The post-processing includes any one of the following: cathodoluminescence detection, cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging. Thus, by applying a superconducting nanowire single-photon detector to cathodoluminescence detection, the detection sensitivity, band coverage, and detection time resolution of cathodoluminescence are greatly improved.

[0032] It should be noted that, in addition to the most basic cathodoluminescence detection, the cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application embodiment can also realize multiple functions such as cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging.

[0033] The methods provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0034] like Figure 2 As shown in the embodiment of this application, a cathodoluminescence detection method based on a superconducting nanowire single-photon detector is provided. This method is applied to the aforementioned data acquisition and processing unit and may include the following steps 201 and 202: Step 201: Receive the detection signal sent by the superconducting nanowire single-photon detector and the measurement position information corresponding to the detection signal sent by the electron microscope.

[0035] Step 202: Based on the measurement location information, determine the current measurement location of the object to be measured, and based on the detection signal, determine the intensity result of the CL signal associated with the current measurement location.

[0036] For example, the above-mentioned cathodoluminescence detection method based on superconducting nanowire single-photon detector is mainly used to detect the fluorescence intensity at a certain location of the object under test.

[0037] like Figure 3As shown in the embodiment of this application, a cathodoluminescence imaging method based on a superconducting nanowire single-photon detector is provided. This method is applied to the aforementioned data acquisition and processing unit and may include the following steps 301 to 303: Step 301: Receive the detection signal sent by the superconducting nanowire single-photon detector and the measurement position information corresponding to the detection signal sent by the electron microscope.

[0038] Step 302: Based on the received measurement location information, determine the current measurement location of the object under test, and based on the received detection signal, determine the intensity result of the CL signal associated with the current measurement location of the object under test, until the intensity result of the CL signal associated with each measurement location of the object under test is obtained.

[0039] Step 303: Reconstruct the image based on the CL signal intensity associated with each measurement position of the object under test to obtain the cathodoluminescence image of the object under test.

[0040] The CL signals associated with different measurement positions of the object under test are obtained by changing the scanning position of the electron beam in the electron microscope.

[0041] For example, such as Figure 4 As shown, the cathodoluminescence imaging method includes the following steps: Cathodoluminescence imaging is achieved using the SNSPD-CL cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application embodiment. This requires using a magnetic lens in an electron scanning microscope to sequentially incident the electron beam onto different positions on the material / sample to be imaged, achieving spatial scanning of the material / sample. Each time the beam moves to a new position, it remains stationary at that position for a period of time. During this time, the cathodoluminescence excited by the electron beam is collected by the collection system and sent to the SNSPD for detection. After the SNSPD outputs a single-photon detection signal, it records and processes the signal, and combines this with the current electron beam position to output a cathodoluminescence intensity result associated with that position. After this, the magnetic lens deflects the electron beam to a new position, and the above process is repeated. After all points within the imaging area have been scanned, a cathodoluminescence intensity image is reconstructed based on the cathodoluminescence intensity results associated with each point.

[0042] like Figure 5 As shown in the embodiment of this application, a cathodoluminescence spectroscopy detection method based on a superconducting nanowire single-photon detector is provided. This method is applied to the aforementioned data acquisition and processing unit and may include the following steps 501 and 502: Step 501: Receive the detection signal sent by the superconducting nanowire single-photon detector and the synchronization signal sent by the Fourier transform spectrometer in the cathode fluorescence spectroscopy processing unit.

[0043] Step 502: Based on the detection signal and the synchronization signal, perform time-correlated single-photon counting to obtain the counting result, and calculate the cathodoluminescence spectrum based on the counting result.

[0044] For example, such as Figure 6 As shown, the procedure for cathodoluminescence photodetection includes: To perform cathodoluminescence spectral measurement using an SNSPD-CL system, the electron beam-excited cathodoluminescence needs to be modulated in an FTS before being fed into the SNSPD. Then, the single-photon detection signal generated by the SNSPD detecting the cathodoluminescence is used to perform time-correlated single-photon counting together with the synchronization signal output from the FTS. After processing the results of the time-correlated single-photon counting, the cathodoluminescence spectrum can be calculated in a host computer using Fourier transform.

[0045] like Figure 7 As shown in the embodiment of this application, a cathodoluminescence spectroscopy imaging method based on a superconducting nanowire single-photon detector is provided. This method is applied to the aforementioned data acquisition and processing unit and may include the following steps 701 to 703: Step 701: Receive the detection signal sent by the superconducting nanowire single-photon detector, the synchronization signal sent by the Fourier transform spectrometer in the cathodoluminescence spectroscopy processing unit, and the measurement position information corresponding to the detection signal sent by the electron microscope; Step 702: Based on the received measurement position information, determine the current measurement position of the object under test, and based on the received detection signal and synchronization signal, determine the single photon count result associated with the current measurement position of the object under test, until the single photon count result associated with each measurement position of the object under test is obtained.

[0046] Step 703: Based on the single-photon count results associated with each measurement position of the object under test, obtain the cathodoluminescence spectrum image of the object under test.

[0047] The single-photon counting result is generated by time-correlated single-photon counting based on the detection signal and the synchronization signal; the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope.

[0048] For example, such as Figure 8 As shown, the procedure for this cathodoluminescence spectroscopy imaging method includes: using an SNSPD-CL system to achieve cathodoluminescence spectroscopy imaging. In specific steps, similar to the cathodoluminescence imaging procedure, a magnetic lens is used to deflect the electron beam to different positions on the material / sample to be imaged. During the dwell time at a certain position, the electron beam is processed according to a similar... Figure 3The procedure for cathodoluminescence spectroscopy measurement involves using FTS modulation to collect cathodoluminescence and recording the single-photon detection signal. Time-correlated single-photon counting is performed between the single-photon signal and the FTS synchronization signal to record the current electron beam position. This process is repeated until all points within the imaging area have been scanned. Finally, based on the time-correlated single-photon count results at each point, the cathodoluminescence spectral image of the entire imaging area is reconstructed.

[0049] It should be noted that the cathodoluminescence detection system based on a superconducting nanowire single-photon detector provided in this application is the first to achieve the detection of weak SPR signals exceeding 1700 nm, verifying the core function of this patent and broadening the detectable range of CL research. Smith-purcell radiation (SPR) refers to the broadband radiation generated in free space when free electrons graze through a metal periodic grating. Its wavelength varies with electron energy and radiation angle, and it has significant research value in micro / nano optoelectronics, vacuum electronics, and other fields. It also has potential applications in broadband tunable miniaturization or on-chip light sources. Currently, on-chip SPR research is usually based on CL systems, with the longest reported radiation wavelength being approximately 1600 nm. Expanding the on-chip SPR coverage to longer wavelength ranges is expected to promote the development of research fields such as infrared elemental analysis and ultra-wideband on-chip light sources.

[0050] The SPR detection process provided in this application includes: ① Place the prepared on-chip structure on the SEM sample stage, adjust the electron microscope image to be clear, and align the free electrons to the desired excitation position.

[0051] ② The on-chip structure was excited by the point electron beam of an electron microscope to generate an SPR signal in the SEM vacuum chamber.

[0052] ③ Collect the generated SPR signal and select different wavelengths of the SPR signal for detection using different filters in the filtering system.

[0053] ④ Count the single-photon detection signals generated by the SNSPD and accumulate the counting results over a period of time.

[0054] ⑤ Turn off the electron beam so that the SPR signal is no longer generated, and count the dark count of SNSPD, accumulating the count results for the same period of time as ④.

[0055] ⑥ You can replace the filter and repeat steps ④ and ⑤ to obtain SPR signals and dark noise data in different bands, and obtain the SPR intensity in different bands through computer data processing.

[0056] like Figure 9The diagram shows the intensity of SPR signals in the 1500-2000 nm and 1750-2250 nm bands obtained after the above steps. The horizontal axis represents the different bands determined by the filters inserted in the filtering system, and the vertical axis represents the signal intensity in Hz, meaning the number of photons detected per second. The light-colored area represents the intensity of dark noise when the electron beam is off, while the dark-colored area represents the intensity exceeding the dark noise when the electron beam is on, corresponding to the SPR signal intensity. The error bars on each part represent the standard error of that part. This result proves that the SNSPD-CL system can detect SPR signals in the 1750-2250 nm band and has the ability to detect weak SPR signals above 1700 nm, surpassing the detection capabilities of traditional CL detection systems.

[0057] It should be noted that the cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method provided in the embodiments of this application are executed by the data acquisition and processing unit in the cathodoluminescence detection system based on the superconducting nanowire single-photon detector.

[0058] Figure 10 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 10As shown, the electronic device may include: a processor 1010, a communications interface 1020, a memory 1030, and a communication bus 1040, wherein the processor 1010, the communications interface 1020, and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 can call logical instructions in the memory 1030 to execute any one of the above-mentioned cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method. The above-mentioned cathodoluminescence detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the measurement position information; and determining the intensity result of the CL signal associated with the current measurement position based on the detection signal. The aforementioned cathodoluminescence imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the intensity result of the CL signal associated with the current measurement position of the object under test based on the received detection signal, until the intensity result of the CL signal associated with each measurement position of the object under test is obtained; performing image reconstruction based on the intensity of the CL signal associated with each measurement position of the object under test to obtain a cathodoluminescence image of the object under test; wherein, the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope. The aforementioned cathodoluminescence spectral detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and a synchronization signal sent by a Fourier transform spectrometer in the cathodoluminescence spectral processing unit; performing time-correlated single-photon counting based on the detection signal and the synchronization signal to obtain the counting result, and calculating the cathodoluminescence spectrum based on the counting result.The aforementioned cathodoluminescence spectral imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector, a synchronization signal sent by the Fourier transform spectrometer in the cathodoluminescence spectral processing unit, and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the single-photon count result associated with the current measurement position of the object under test based on the received detection signal and synchronization signal, until the single-photon count result associated with each measurement position of the object under test is obtained; obtaining the cathodoluminescence spectral image of the object under test based on the single-photon count result associated with each measurement position of the object under test; wherein, the single-photon count result is generated by time-correlated single-photon counting based on the detection signal and synchronization signal; the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope.

[0059] Furthermore, the logical instructions in the aforementioned memory 1030 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0060] On the other hand, this application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by a computer, the computer can perform any of the above-mentioned cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method. The above-mentioned cathodoluminescence detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the measurement position information; and determining the intensity result of the CL signal associated with the current measurement position based on the detection signal. The aforementioned cathodoluminescence imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the intensity result of the CL signal associated with the current measurement position of the object under test based on the received detection signal, until the intensity result of the CL signal associated with each measurement position of the object under test is obtained; performing image reconstruction based on the intensity of the CL signal associated with each measurement position of the object under test to obtain a cathodoluminescence image of the object under test; wherein, the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope. The aforementioned cathodoluminescence spectral detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and a synchronization signal sent by a Fourier transform spectrometer in the cathodoluminescence spectral processing unit; performing time-correlated single-photon counting based on the detection signal and the synchronization signal to obtain the counting result, and calculating the cathodoluminescence spectrum based on the counting result.The aforementioned cathodoluminescence spectral imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector, a synchronization signal sent by the Fourier transform spectrometer in the cathodoluminescence spectral processing unit, and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the single-photon count result associated with the current measurement position of the object under test based on the received detection signal and synchronization signal, until the single-photon count result associated with each measurement position of the object under test is obtained; obtaining the cathodoluminescence spectral image of the object under test based on the single-photon count result associated with each measurement position of the object under test; wherein, the single-photon count result is generated by time-correlated single-photon counting based on the detection signal and synchronization signal; the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope.

[0061] In another aspect, this application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, performs any one of the above-described cathodoluminescence detection method, cathodoluminescence imaging method, cathodoluminescence spectral detection method, and cathodoluminescence spectral imaging method. The above-described cathodoluminescence detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the measurement position information; and determining the intensity result of the CL signal associated with the current measurement position based on the detection signal. The aforementioned cathodoluminescence imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the intensity result of the CL signal associated with the current measurement position of the object under test based on the received detection signal, until the intensity result of the CL signal associated with each measurement position of the object under test is obtained; performing image reconstruction based on the intensity of the CL signal associated with each measurement position of the object under test to obtain a cathodoluminescence image of the object under test; wherein, the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope. The aforementioned cathodoluminescence spectral detection method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector and a synchronization signal sent by a Fourier transform spectrometer in the cathodoluminescence spectral processing unit; performing time-correlated single-photon counting based on the detection signal and the synchronization signal to obtain the counting result, and calculating the cathodoluminescence spectrum based on the counting result. The aforementioned cathodoluminescence spectral imaging method based on a superconducting nanowire single-photon detector includes: receiving a detection signal sent by the superconducting nanowire single-photon detector, a synchronization signal sent by the Fourier transform spectrometer in the cathodoluminescence spectral processing unit, and measurement position information corresponding to the detection signal sent by an electron microscope; determining the current measurement position of the object under test based on the received measurement position information, and determining the single-photon count result associated with the current measurement position of the object under test based on the received detection signal and synchronization signal, until the single-photon count result associated with each measurement position of the object under test is obtained; obtaining the cathodoluminescence spectral image of the object under test based on the single-photon count result associated with each measurement position of the object under test; wherein, the single-photon count result is generated by time-correlated single-photon counting based on the detection signal and synchronization signal; the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope.

[0062] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0063] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A cathodoluminescence detection system based on a superconducting nanowire single-photon detector, characterized in that, include: The system includes a cathodoluminescence spectroscopy processing unit, a superconducting nanowire single-photon detector, and a data acquisition and processing unit. The cathodoluminescence spectroscopy processing unit is used to receive the cathodoluminescence CL signal generated by the electron microscope, preprocess the CL signal, and transmit the preprocessed CL signal to the superconducting nanowire single-photon detector. The superconducting nanowire single-photon detector is used to detect the preprocessed CL signal and input the generated detection signal into the data acquisition and processing unit. The data acquisition and processing unit is used to post-process the received detection signals and generate processing results; The preprocessing includes at least one of the following: spectral modulation of the received CL signal, and filtering of the noise band in the received CL signal; the postprocessing includes any one of the following: cathodoluminescence detection, cathodoluminescence imaging, cathodoluminescence spectral detection, and cathodoluminescence spectral imaging.

2. The system according to claim 1, characterized in that, The cathode fluorescence spectroscopy processing unit includes a Fourier transform spectrometer and a filtering system; the data acquisition and processing unit includes a time-to-digital converter and a host computer.

3. The system according to claim 2, characterized in that, The cathodoluminescence spectral processing unit is specifically used to perform spectral modulation on the received CL signal using a Fourier transform spectrometer when the post-processing is cathodoluminescence spectral detection or cathodoluminescence spectral imaging, and to filter the noise band in the spectrally modulated CL signal. The data acquisition and processing unit is specifically used to input the received detection signal and synchronization signal into the time-to-digital converter for recording, and input the recording result into the host computer for post-processing; The synchronization signal is output by the Fourier transform spectrometer; the synchronization signal is used to characterize the position of the moving mirror of the interferometer in the Fourier transform spectrometer.

4. The system according to claim 1, characterized in that, The cathode fluorescence spectral processing unit includes a filtering system; the data acquisition and processing unit includes a time-to-digital converter and a host computer.

5. The system according to claim 4, characterized in that, The data acquisition and processing unit includes: a time-to-digital converter and a host computer; The cathode fluorescence spectral processing unit is specifically used to filter the noise band in the received CL signal when the post-processing is cathode fluorescence detection or cathode fluorescence imaging. The data acquisition and processing unit is specifically used to input the received detection signal into the time-to-digital converter for recording, and to input the recording result into the host computer for post-processing.

6. A cathodoluminescence detection method based on a superconducting nanowire single-photon detector, characterized in that, Applied to a cathodoluminescence detection system based on a superconducting nanowire single-photon detector as described in any one of claims 1 to 5; The cathode fluorescence detection system includes: a superconducting nanowire single-photon detector; The method includes: Receive the detection signal sent by the superconducting nanowire single-photon detector and the measurement position information corresponding to the detection signal sent by the electron microscope; Based on the measurement location information, the current measurement location of the object under test is determined, and the intensity result of the CL signal associated with the current measurement location is determined based on the detection signal.

7. A cathodoluminescence imaging method based on a superconducting nanowire single-photon detector, characterized in that, Applied to a cathodoluminescence detection system based on a superconducting nanowire single-photon detector as described in any one of claims 1 to 5; The cathode fluorescence detection system includes: a superconducting nanowire single-photon detector; The method includes: Receive the detection signal sent by the superconducting nanowire single-photon detector and the measurement position information corresponding to the detection signal sent by the electron microscope; Based on the received measurement location information, the current measurement location of the object under test is determined, and the intensity result of the CL signal associated with the current measurement location of the object under test is determined based on the received detection signal, until the intensity result of the CL signal associated with each measurement location of the object under test is obtained; Image reconstruction is performed based on the CL signal intensity associated with each measurement location of the object under test to obtain the cathodoluminescence image of the object under test; The CL signals associated with different measurement positions of the object under test are obtained by changing the scanning position of the electron beam in the electron microscope.

8. A cathodoluminescence spectroscopy detection method based on a superconducting nanowire single-photon detector, characterized in that, Applied to a cathodoluminescence detection system based on a superconducting nanowire single-photon detector as described in any one of claims 1 to 5; The cathodoluminescence detection system includes: a cathodoluminescence spectral processing unit and a superconducting nanowire single-photon detector; The method includes: It receives the detection signal sent by the superconducting nanowire single-photon detector and the synchronization signal sent by the Fourier transform spectrometer in the cathode fluorescence spectroscopy processing unit. Based on the detection signal and the synchronization signal, time-correlated single-photon counting is performed to obtain the counting result, and the cathodoluminescence spectrum is calculated based on the counting result.

9. A cathodoluminescence spectroscopy imaging method based on a superconducting nanowire single-photon detector, characterized in that, Applied to a cathodoluminescence detection system based on a superconducting nanowire single-photon detector as described in any one of claims 1 to 5; The cathodoluminescence detection system includes: a cathodoluminescence spectral processing unit and a superconducting nanowire single-photon detector; The method includes: It receives the detection signal sent by the superconducting nanowire single-photon detector, the synchronization signal sent by the Fourier transform spectrometer in the cathode fluorescence spectroscopy processing unit, and the measurement position information corresponding to the detection signal sent by the electron microscope; Based on the received measurement location information, the current measurement location of the object under test is determined, and based on the received detection signal and synchronization signal, the single photon count result associated with the current measurement location of the object under test is determined, until the single photon count result associated with each measurement location of the object under test is obtained; Based on the single-photon count results associated with each measurement position of the object under test, the cathodoluminescence spectrum image of the object under test is obtained; The single-photon counting result is generated by time-correlated single-photon counting based on the detection signal and the synchronization signal; the CL signal associated with different measurement positions of the object under test is obtained by changing the scanning position of the electron beam in the electron microscope.

10. An electronic device, characterized in that, Including the cathodoluminescence detection system based on a superconducting nanowire single-photon detector as described in any one of claims 1 to 5.

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