Time-resolved fluorescence imaging system based on interference energy resolution and carrier diffusion measurement method

Abstract

The invention discloses a time-resolved fluorescence imaging system based on interference energy resolution and a carrier diffusion measurement method. The time-resolved fluorescence imaging system comprises a laser output unit, an objective table, an objective lens, a beam splitter, a light filtering unit, an interferometer, an optical amplification unit and a single photon detection unit, the objective table is used for placing a sample; the laser output unit is used for outputting collimated and expanded laser; the laser is reflected to the objective lens through the beam splitter and is focused to a preset position of the sample through the objective lens; fluorescence generated after the sample is excited and reflected laser are transmitted to the light filtering unit through the objective lens and the beam splitter, and the light filtering unit is used for blocking the laser and transmitting the fluorescence to the interferometer; the interferometer is used for dividing the fluorescence into first fluorescence and second fluorescence with preset delay time; the optical amplification unit is used for optically amplifying the first fluorescent light and the second fluorescent light; and the single photon detection unit is used for scanning the first fluorescence and the second fluorescence which are optically amplified. According to the invention, energy-resolved carrier diffusion measurement can be rapidly carried out.

Description

Technical Field

[0001] This invention relates to the field of time-resolved fluorescence imaging technology, and in particular to a time-resolved fluorescence imaging system and carrier diffusion measurement method based on interferometric energy resolution. Background Technology

[0002] The main existing methods for measuring carrier diffusion constants include scanning photocurrent imaging (SPI), transient fluorescence spectroscopy (TFS), and steady-state fluorescence imaging (SFI). SPI requires contact electrodes, which can damage materials and necessitates micro / nano-fabrication of the sample. It is unsuitable for environmentally sensitive materials and has strict sample selection requirements. Its advantage is that it can measure non-fluorescent materials. Transient absorption imaging typically uses higher laser power, has longer measurement times, causes greater sample damage, and has high system setup costs and complexity. Its advantage is that the measurement time resolution can reach the femtosecond level. While SFI can rapidly measure diffusion distance, it suffers from difficult data analysis, large measurement errors, and a lack of time resolution in the results. All these methods suffer from low measurement efficiency, missing spatial or temporal information, or high equipment requirements, making it difficult to achieve high-throughput, high-accuracy, and low-destructive carrier diffusion measurements. Summary of the Invention

[0003] To address the technical problems existing in the background art, this invention proposes a time-resolved fluorescence imaging system and a carrier diffusion measurement method based on interferometric energy resolution.

[0004] The present invention proposes a time-resolved fluorescence imaging system based on interference energy resolution, comprising: a laser output unit, a stage, an objective lens, a beam splitter, a filter unit, an interferometer, an optical magnification unit, and a single-photon detection unit; The stage is used to place the sample; the laser output unit is used to output collimated and expanded laser beams; the beam splitter is used to reflect the collimated and expanded laser beams onto the objective lens; the objective lens is used to focus the laser beam onto the preset position of the sample and transmit the fluorescence generated after the sample is excited and the laser beam reflected by the sample to the beam splitter. The beam splitter is also used to transmit fluorescence and reflected laser light onto the filter unit; the filter unit is used to filter out the laser light and transmit fluorescence onto the interferometer; the interferometer is used to split the fluorescence into a first fluorescence and a second fluorescence with a predetermined delay time; the optical amplification unit is used to optically amplify the first fluorescence and the second fluorescence respectively; the single-photon detection unit is used to scan and measure the optically amplified first fluorescence and the second fluorescence respectively to obtain time-resolved fluorescence emission spectra with different fluorescence emission energies.

[0005] Preferably, the single-photon detection unit includes a single-photon detector and an electric displacement stage. The single-photon detector is mounted on the electric displacement stage, which is used to move the single-photon detector along a preset detection direction.

[0006] Preferably, the angle of the nonlinear crystal in the interferometer is adjustable.

[0007] Preferably, the filtering unit includes a long-pass filter for filtering out laser-retained fluorescence.

[0008] Preferably, the laser output unit includes a laser generator and a shaping component, wherein the laser generator is used to generate laser light, and the shaping component is used to collimate and expand the laser beam.

[0009] Preferably, the shaping assembly includes: a second reflector, a third reflector, a fourth reflector, a second lens, a spatial filter, and a third lens; The laser beam is focused onto the spatial filter by the third lens, filtered into a Gaussian spot by the pinhole of the spatial filter, then collimated and expanded by the second lens, and then passed through the fourth, third and second reflectors in sequence before being output to the beam splitter.

[0010] Preferably, it also includes a controller, and the single-photon detection unit is electrically connected to the controller.

[0011] Secondly, this invention also proposes a carrier diffusion measurement method based on interference energy resolution, comprising: The time-resolved fluorescence imaging system based on interferometric energy resolution described in any one of the first aspects is used to collect images of preset positions in the fluorescence spot of the sample, thereby obtaining fluorescence emission attenuation images of different preset positions of the fluorescence spot. Based on the fluorescence emission attenuation images at different preset positions of the fluorescent spot, a time-space resolved fluorescence emission spectrum is obtained; The carrier diffusion constant of the sample is obtained based on the time-space resolved fluorescence emission spectrum.

[0012] Preferably, the carrier diffusion constant of the sample is obtained based on the time-resolved fluorescence emission spectrum, specifically including: Normalize the fluorescence emission decay images at different preset delay times in the time-resolved fluorescence emission spectrum to obtain the spatial distribution map of carrier concentration evolution over time. Gaussian fitting was performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time. The carrier diffusion constant of the sample is calculated based on the change of the carrier spatial distribution profile over time.

[0013] Preferably, Gaussian fitting is performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time, specifically including: Step a: Extract the fluorescence decay curve position distribution map of the preset fluorescence emission energy from the spatial distribution map of the carrier concentration evolution over time, and select the spatial distribution curve of the carrier concentration at a certain preset delay time from the fluorescence decay curve position distribution map of the preset fluorescence emission energy. Step b: Fit the spatial distribution curve of carrier concentration under the preset delay time using a Gaussian distribution function to obtain the spatial distribution profile of carriers under the preset delay time. Step c, repeat steps a and b until the preset number of times to obtain the carrier space distribution profile under different preset delay times; based on the carrier space distribution profile under different preset delay times, obtain the relationship between the carrier space distribution profile and time.

[0014] The proposed time-resolved fluorescence imaging system and carrier diffusion measurement method based on interferometric energy resolution have a simple system structure, making them easier to build and operate. Furthermore, the combination of an interferometer and a single-photon detection unit enables rapid detection of time-resolved fluorescence emission spectra with different fluorescence emission energies. This facilitates subsequent carrier diffusion measurement by a controller or host computer based on the time-resolved fluorescence emission spectrum. The carrier diffusion constant in the luminescent material can be obtained with only optical excitation and detection, making it suitable for various luminescent materials, thin films, and micro / nano structures, as well as other vulnerable materials. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a time-resolved fluorescence imaging system based on interferometric energy resolution in one embodiment of the present invention.

[0016] Figure 2 The data processing results are shown in one embodiment of the present invention; wherein, (a) is the fluorescence emission spectrum of the sample being measured, and (b) is the relationship between the spatial distribution profile of the carriers with different fluorescence emission energies of the sample and the change over time. Detailed Implementation

[0017] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] Firstly, referring to Figure 1 The present invention proposes a time-resolved fluorescence imaging system based on interference energy resolution, comprising: a laser output unit, an objective lens 1, a beam splitter 2, a filter unit 3, an interferometer 4, an optical magnification unit, and a single-photon detection unit; The laser output unit is used to output collimated and expanded laser beams; the beam splitter 2 is used to reflect the collimated and expanded laser beams onto the objective lens 1; the objective lens 1 is used to focus the laser beam onto a preset position on the sample and transmit the fluorescence generated by the sample after it is excited and the laser beam reflected by the sample onto the beam splitter 2. Beam splitter 2 is also used to transmit fluorescence and reflected laser light onto filter unit 3; filter unit 3 is used to filter out laser light and transmit fluorescence onto interferometer 4; interferometer 4 is used to split fluorescence into first fluorescence and second fluorescence with predetermined delay time; optical amplification unit is used to optically amplify the first fluorescence and second fluorescence respectively. The single-photon detection unit is used to scan and measure the optically amplified first and second fluorescence to obtain the time-resolved fluorescence emission spectrum.

[0019] In practice, the laser output unit outputs collimated and expanded laser light to the beam splitter 2. The beam splitter 2 reflects the laser light onto the objective lens 1, which focuses the laser light onto the sample and transmits the fluorescence generated by the sample after excitation and the reflected laser light to the beam splitter 2. The beam splitter 2 transmits the fluorescence and the reflected laser light to the filter unit 3, which filters out the laser light and transmits the fluorescence light to the interferometer 4. The interferometer 4 separates the fluorescence into a first fluorescence and a second fluorescence with a predetermined delay time. The optical amplification unit optically amplifies the first fluorescence and the second fluorescence respectively. The single-photon detection unit scans and measures the optically amplified first fluorescence and the second fluorescence to obtain a fluorescence emission attenuation image at the same position on the sample. By repeating this process, fluorescence emission attenuation images at different positions on the sample can be obtained, i.e., time-resolved fluorescence emission spectra, which is beneficial for subsequent controllers or host computers to perform carrier diffusion measurements based on the time-resolved fluorescence emission spectra.

[0020] This invention has a simple structure, making it easier to build and operate. Moreover, through the cooperation of the interferometer 4 and the single-photon detection unit, it achieves rapid detection of time-resolved fluorescence emission spectrum, which is beneficial for subsequent controllers or host computers to perform carrier diffusion measurement based on time-resolved fluorescence emission spectrum, and to perform optical excitation and detection. It is applicable to carrier diffusion measurement of various luminescent materials.

[0021] The single-photon detection unit in this embodiment includes a single-photon detector 7 and an electric displacement stage 8. The single-photon detector 7 is mounted on the electric displacement stage 8, and the optical amplification unit is used to amplify the first fluorescence and the second fluorescence to the detection plane of the single-photon detector 7. The electric displacement stage 8 is used to drive the single-photon detector 7 to move along a preset detection direction.

[0022] With this configuration, the single-photon detection unit in this embodiment can scan and measure a radial line (one-dimensional) of the magnified fluorescence spot to obtain the fluorescence intensity at different positions at the same time, which facilitates the subsequent acquisition of the spatial distribution of carrier concentration.

[0023] The preset detection direction is either a horizontal or vertical line passing through the center of the fluorescent spot.

[0024] It is important to understand that a nonlinear crystal is present within the interferometer 4. After passing through the interferometer 4, the fluorescence beam will generate two beams with a certain time delay at almost the same position. In this embodiment, the angle of the nonlinear crystal in the interferometer 4 is adjustable. That is, by rotating the angle of the nonlinear crystal, this embodiment can control the time delay of the first and second fluorescence. By measuring the dynamics under different crystal deflection angles, and in conjunction with the single-photon detector 7, energy-resolved fluorescence dynamics attenuation measurement can be achieved after Fourier transform.

[0025] The filter unit 3 in this embodiment includes a long-pass filter to filter out laser light while retaining fluorescence.

[0026] Of course, this embodiment also includes a stage for placing samples, such as monolayer transition metal sulfide materials, metal halide perovskites, and other luminescent solid materials.

[0027] In this embodiment, objective lens 1 is used to focus and vertically irradiate a preset position on the sample to excite the generation of non-equilibrium charge carriers (electron-hole pairs), forming an initial charge carrier concentration distribution. After stimulated emission, the charge carriers generate fluorescence. The charge carrier concentration is proportional to the fluorescence intensity. By measuring the change in fluorescence intensity distribution, the change in charge carrier concentration distribution can be monitored.

[0028] In this embodiment, the laser output unit includes a laser generator 15 and a shaping component. The laser generator 15 is used to generate laser light, and the shaping component is used to collimate and expand the laser beam to form a near-diffraction-limited Gaussian spot to excite the sample to generate non-equilibrium charge carriers.

[0029] In a further embodiment, the shaping assembly includes: a second reflector 10, a third reflector 9, a fourth reflector 11, a second lens 12, a spatial filter 13, and a third lens 14; The laser beam is focused onto the spatial filter 13 by the third lens 14, and then filtered into a Gaussian spot by the pinhole of the spatial filter 13. It is then collimated and expanded by the second lens 12, and then passed through the fourth reflector 11, the third reflector 9 and the second reflector 10 in sequence before being output to the beam splitter 2.

[0030] The third lens 14 is used to focus the laser onto the spatial filter 13; the spatial filter 13 is used to perform pinhole filtering on the laser so that the laser spot is a Gaussian spot; the second lens 12 is used to collimate and expand the laser with the Gaussian spot to adjust the size of the spot; the fourth reflector 11, the third reflector 9 and the second reflector 10 work together to adjust the parallelism of the laser so that the collimated and expanded laser is incident on the beam splitter 2.

[0031] With this configuration, this embodiment can perform spatial filtering, parallelism adjustment, and spot size control on the laser, ensuring that the laser spot is a Gaussian spot close to the diffraction limit after reaching the sample plane.

[0032] In this embodiment, the laser generator 15 is used to provide picosecond monochromatic pulse laser.

[0033] Specifically, the laser generator 15 provides a picosecond monochromatic pulse laser. After passing through the third lens 14, spatial filter 13, second lens 12, fourth reflector 11, third reflector 9, and second reflector 10, the pulse laser forms a near-diffraction-limited Gaussian spot. The Gaussian spot is reflected by the beam splitter 2 onto the objective lens 1. The objective lens 1 focuses the pulse laser onto the sample. After the sample is focused, non-equilibrium carriers are generated. The non-equilibrium carriers recombine to generate fluorescence. The fluorescence returns to the beam splitter 2 through the objective lens 1. The beam splitter 2 transmits the fluorescence onto the filter. The fluorescence filtered by the filter is generated by the interferometer 4 to achieve energy resolution. After being optically magnified by the reflector and the first lens 6, it enters the single-photon detector 7.

[0034] In this embodiment, a controller is also included, and the single-photon detection unit is electrically connected to the controller.

[0035] In this embodiment, the interferometer and single-photon detection unit are communicatively connected to the controller, that is, the interferometer 4, the single-photon detector 7, and the electric displacement stage 8 are all communicatively connected to the controller.

[0036] Secondly, this invention also proposes a carrier diffusion measurement method based on interference energy resolution, comprising: The time-resolved fluorescence imaging system based on interferometric energy resolution described in any one of the first aspects is used to collect images of preset positions in the fluorescence spot of the sample, thereby obtaining fluorescence emission attenuation images of different preset positions of the fluorescence spot. Based on the fluorescence emission attenuation images at different preset positions of the fluorescent spot, a time-space resolved fluorescence emission spectrum is obtained; The carrier diffusion constant of the sample is obtained based on the time-space resolved fluorescence emission spectrum.

[0037] This invention realizes a non-contact, high spatial resolution, and energy-resolved method for measuring the carrier diffusion constant, which can obtain the carrier diffusion constant of luminescent materials with only optical excitation and detection.

[0038] In this embodiment, the carrier diffusion constant of the sample is obtained based on the time-resolved fluorescence emission spectrum, specifically including: Normalize the fluorescence emission decay images at different preset delay times in the time-resolved fluorescence emission spectrum to obtain the spatial distribution map of carrier concentration evolution over time. Gaussian fitting was performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time. The carrier diffusion constant of the sample is calculated based on the change of the carrier spatial distribution profile over time.

[0039] Since fluorescence intensity is proportional to local non-equilibrium carrier concentration, this embodiment normalizes the fluorescence images at different delay times to obtain a spatial distribution map of carrier concentration evolution over time. Then, Gaussian fitting is performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the carrier spatial distribution profile and time. Based on the relationship between the carrier spatial distribution profile and time, the carrier diffusion constant of the sample is calculated.

[0040] Among them, Gaussian fitting is performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time, specifically including: Step a: Extract the fluorescence decay curve position distribution map of the preset fluorescence emission energy from the spatial distribution map of the carrier concentration evolution over time, and select the spatial distribution curve of the carrier concentration at a certain preset delay time from the fluorescence decay curve position distribution map of the preset fluorescence emission energy. Step b: Fit the spatial distribution curve of carrier concentration under the preset delay time using a Gaussian distribution function to obtain the spatial distribution profile of carriers under the preset delay time. Step c: Repeat steps a and b until the preset number of times (i.e., traverse different preset delay times) to obtain the carrier space distribution profile under different preset delay times; based on the carrier space distribution profile under different preset delay times, obtain the relationship between the carrier space distribution profile and time.

[0041] The carrier diffusion equation is as follows: ; In the formula, n is the carrier concentration, D is the carrier diffusion constant, and k is the first-order recombination rate constant. Let t be the Nabla operator, and t represent time. Indicates distance.

[0042] Specifically, the relationship between the spatial distribution profile of the charge carriers and time is as follows: ; In the formula, The vector represents the spatial distribution profile of the charge carriers, t represents time, and D represents the carrier diffusion constant.

[0043] The present invention will now be described in conjunction with specific embodiments.

[0044] Example 1 like Figure 1 As shown, the present invention proposes a carrier diffusion measurement method based on interferometric energy resolution, comprising: A time-resolved fluorescence imaging system based on interferometric energy resolution was used to collect images of preset positions in the fluorescence spot of the sample, and fluorescence emission attenuation images of different preset positions of the fluorescence spot were obtained. Based on the fluorescence emission attenuation images at different preset positions of the fluorescent spot, a time-space resolved fluorescence emission spectrum is obtained; The carrier diffusion constant of the sample is obtained based on the time-space resolved fluorescence emission spectrum; The time-resolved fluorescence imaging system based on interferometric energy resolution includes: a stage, a laser generator 15, an objective lens 1, a beam splitter 2, a filter, an interferometer 4, a first reflector 5, a first lens 6, an electrically driven stage 8, a single-photon detection unit, a controller, and a spot shaping assembly; the interferometer and the single-photon detection unit are communicatively connected to the controller; the spot shaping assembly includes: a second reflector 10, a third reflector 9, a fourth reflector 11, a second lens 12, a spatial filter 13, and a third lens 14; the single-photon detection unit includes a single-photon detector 7 and an electrically driven stage 8 for adjusting the position of the single-photon detector 7; a perovskite material sample is placed on the stage; In practice, the laser generator 15 provides a picosecond monochromatic pulsed laser. The pulsed laser passes through the third lens 14, spatial filter 13, second lens 12, fourth reflector 11, third reflector 9, and second reflector 10 to form a near-diffraction-limited Gaussian spot. This Gaussian spot is reflected by the beam splitter 2 onto the objective lens 1. The objective lens 1 focuses the pulsed laser onto a preset position on the perovskite material. After being focused, the perovskite material generates non-equilibrium carriers, which produce fluorescence. The fluorescence returns through the objective lens 1 to the beam splitter 2, which transmits the fluorescence onto a filter. The fluorescence filtered by the filter is generated by the interferometer 4 to achieve energy resolution. After being optically focused by the mirror and the first lens 6, it enters the detection plane of the single-photon detector 7. The electric displacement stage 8 drives the single-photon detector 7 to scan and measure a radial line (one-dimensional) of the magnified fluorescence spot to obtain the fluorescence emission attenuation image at the preset position. The above steps are repeated until the preset position has traversed the preset position set. After the preset position has traversed the preset position set, the time-resolved fluorescence emission spectrum is obtained based on the fluorescence emission attenuation images of different preset positions of the perovskite material. After normalizing the fluorescence images at different preset delay times in the time-resolved fluorescence emission spectrum, the spatial distribution map of carrier concentration evolution over time can be obtained. Then, Gaussian fitting is performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the carrier spatial distribution profile and time. Based on the relationship between the carrier spatial distribution profile and time, the carrier diffusion constant of the perovskite material is calculated.

[0045] in, Figure 2 (a) shows the fluorescence emission spectrum of the sample being measured, and (b) shows the relationship between the spatial distribution profile of the carriers at different fluorescence emission energies of the sample and time.

[0046] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A time-resolved fluorescence imaging system based on interferometric energy resolution, characterized in that, include: Laser output unit, stage, objective lens, beam splitter, filter unit, interferometer, optical magnification unit, and single-photon detection unit; The stage is used to place the sample; the laser output unit is used to output collimated and expanded laser beams; the beam splitter is used to reflect the collimated and expanded laser beams onto the objective lens. The objective lens is used to focus the laser onto a preset position on the sample and transmit the fluorescence generated by the sample after it is excited and the laser reflected by the sample to the beam splitter. The beam splitter is also used to transmit fluorescence and reflected laser light onto the filter unit; the filter unit is used to filter out the laser light and transmit fluorescence onto the interferometer; the interferometer is used to split the fluorescence into a first fluorescence and a second fluorescence with a predetermined delay time; the optical amplification unit is used to optically amplify the first fluorescence and the second fluorescence respectively; the single-photon detection unit is used to scan and measure the optically amplified first fluorescence and the second fluorescence to obtain a fluorescence emission attenuation image at a predetermined position of the sample.

2. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 1, characterized in that, The single-photon detection unit includes a single-photon detector and an electric displacement stage. The single-photon detector is mounted on the electric displacement stage, which is used to move the single-photon detector along a preset detection direction.

3. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 1, characterized in that, The angle of the nonlinear crystal in the interferometer is adjustable.

4. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 1, characterized in that, The filtering unit includes a long-pass filter for filtering out laser-retained fluorescence.

5. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 1, characterized in that, The laser output unit includes a laser generator and a shaping component. The laser generator is used to generate laser light, and the shaping component is used to collimate and expand the laser beam.

6. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 5, characterized in that, The shaping assembly includes: a second mirror, a third mirror, a fourth mirror, a second lens, a spatial filter, and a third lens; the laser is focused onto the spatial filter by the third lens, filtered into a Gaussian spot by the pinhole of the spatial filter, then collimated and expanded by the second lens, and then sequentially passed through the fourth mirror, the third mirror, and the second mirror before being output to the beam splitter.

7. The time-resolved fluorescence imaging system based on interferometric energy resolution according to claim 1, characterized in that, It also includes a controller, with the single-photon detection unit electrically connected to the controller.

8. A carrier diffusion measurement method based on interferometric energy resolution, characterized in that, include: The time-resolved fluorescence imaging system based on interferometric energy resolution as described in any one of claims 1-7 is used to collect images of preset positions in the fluorescence spot of the sample, thereby obtaining fluorescence emission attenuation images of different preset positions of the fluorescence spot. Based on the fluorescence emission attenuation images at different preset positions of the fluorescent spot, a time-space resolved fluorescence emission spectrum is obtained; The carrier diffusion constant of the sample is obtained based on the time-space resolved fluorescence emission spectrum.

9. The carrier diffusion measurement method based on interferometric energy resolution according to claim 8, characterized in that, Based on the time-space resolved fluorescence emission spectrum, the carrier diffusion constant of the sample is obtained, specifically including: Normalize the fluorescence emission decay images at different preset delay times in the time-space resolved fluorescence emission spectrum to obtain a spatial distribution map of the carrier concentration distribution evolving over time. Gaussian fitting was performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time. The carrier diffusion constant of the sample is calculated based on the change of the carrier spatial distribution profile over time.

10. The carrier diffusion measurement method based on interferometric energy resolution according to claim 9, characterized in that, Gaussian fitting was performed on the spatial distribution map of carrier concentration evolution over time based on the carrier diffusion equation to obtain the relationship between the spatial distribution profile of carriers and time, specifically including: Step a: Extract the fluorescence decay curve position distribution map of the preset fluorescence emission energy from the spatial distribution map of the carrier concentration evolution over time, and select the spatial distribution curve of the carrier concentration at a certain preset delay time from the fluorescence decay curve position distribution map of the preset fluorescence emission energy. Step b: Fit the spatial distribution curve of carrier concentration under the preset delay time using a Gaussian distribution function to obtain the spatial distribution profile of carriers under the preset delay time. Step c, repeat steps a and b until the preset number of times to obtain the carrier space distribution profile under different preset delay times; based on the carrier space distribution profile under different preset delay times, obtain the relationship between the carrier space distribution profile and time.

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