Multiscale time-resolved spectrometer

Abstract

The invention discloses a multi-scale time-resolved spectrometer, comprising a light source module and a sample chamber. A beam splitter, a modulator, an amplifier and a light generating module are sequentially arranged on the optical path from the light source module to the sample chamber. The light generating module comprises a pump light generating module and a detection light generating module. An optical delay module is arranged on the optical path from the modulator to the pump light generating module or the detection light generating module. An electronic delay module is arranged between the light source module and the modulator. The optical delay and the electronic delay are combined to realize time delay in multiple time scales from femtoseconds to milliseconds, complete multi-scale time-resolved spectrum measurement, and obtain time-resolved spectrum from micro to macro. The invention can be realized on the same set of devices, saving costs and improving data acquisition efficiency and accuracy.

Description

Technical Field

[0001] The invention relates to a spectrometer, in particular to a multi-scale time-resolved spectrometer. Background Art

[0002] In the fields of physics, chemistry, biology, materials, etc., it is necessary to understand the changes in the state of things over time when they are stimulated by external factors, also known as pumping. That is, to study the dynamic evolution of things through time resolution methods, such as studying the dynamic changes of physical and chemical parameters such as molecular structure, carrier energy, and phonon temperature of solar cell materials, light-emitting diodes, photocatalysis, two-dimensional materials, photosynthesis, etc. after optical pump pulse excitation. Time-resolved spectroscopy, from the time scale, time-resolved spectroscopy with a time scale of several femtoseconds to tens of nanoseconds can be achieved in the same device through the method of optical delay. Due to the limitation of the optical delay method, 1 nanosecond requires the delay line to move 30 cm of optical path, so the longest delay can generally only be tens of nanoseconds (10 nanoseconds corresponds to 3 meters of optical path), which cannot meet the needs of studying dynamics in a larger time scale range. Using two sets of time resolution systems will result in high research costs and limit the efficiency and accuracy of the research. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a multi-scale time-resolved spectrometer to solve the problem that a single optical delay spectrometer cannot meet the needs of dynamic research in a larger time scale range, and the two systems have high costs and low efficiency and accuracy.

[0004] Technical solution: The multi-scale time-resolved spectrometer described in the present invention includes a light source module and a sample chamber. A beam splitter, a modulator, an amplifier and a light generating module are sequentially arranged on the optical path from the light source module to the sample chamber. The light generating module includes a pump light generating module and a detection light generating module. An optical delay module is arranged on the optical path from the modulator to the pump light generating module or the detection light generating module. An electronic delay module is arranged between the light source module and the modulator. After the light source module generates laser, it is split by a beam splitter. The light divided into multiple beams is processed by modulators to form seed lights with different repetition frequencies. The seed lights with different repetition frequencies are amplified by amplifiers to form multi-channel laser pulses. The multi-channel laser pulses output corresponding optical signals through the pump light generating module and the detection light generating module respectively. The modulators of the pump light and the detection light are triggered by the electronic delay module to realize the injection of seed light into the amplifier at different times. The optical path difference between the pump light and the detection light reaching the sample is changed in combination with the optical delay module to realize the control of the time difference between the pump light and the detection light reaching the sample.

[0005] It also includes a detector and a data acquisition module. The detector receives the detection light passing through the sample. The data acquisition module is connected to the detector signal to collect at least one of the voltage, current, photon count or photoelectron count output by the detector under different delays.

[0006] The modulator includes a pump optical path modulator and a detection optical path modulator, and the amplifier includes a pump optical path amplifier and a detection optical path amplifier.

[0007] The light source module is a femtosecond laser or a picosecond laser.

[0008] The modulator is an acousto-optic modulator or an electro-optic modulator.

[0009] The amplifier is a fiber amplifier, a regenerative amplifier or a disk laser amplifier.

[0010] The beam splitter is at least one of a fiber beam splitter and a beam splitter.

[0011] The electronic delay module is a pulse delay generator circuit.

[0012] Beneficial effects: The combination of optical delay and electronic delay in the present invention can realize time delay in multiple time scales from femtoseconds to milliseconds, complete multi-scale time-resolved spectral measurement, and obtain time-resolved spectra from micro to macro. The present invention can realize multi-scale time-resolved spectra from femtoseconds, picoseconds, nanoseconds, microseconds to milliseconds on the same set of devices, saving costs and improving data acquisition efficiency and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic structural diagram of Example 1;

[0014] Figure 2 is a schematic structural diagram of Example 2;

[0015] Figure 3 is a schematic structural diagram of Example 3;

[0016] Figure 4 is a schematic structural diagram of Example 4;

[0017] Figure 5 is a schematic structural diagram of Example 5;

[0018] Figure 6 is a schematic structural diagram of Example 6;

[0019] Figure 7 is a schematic structural diagram of Example 7;

[0020] Figure 8 is a schematic structural diagram of Example 8;

[0021] Fig. 9 It is a structural schematic diagram of Example 9. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with embodiments and drawings.

[0023] Example 1

[0024] like Figure 1As shown, the multi-scale time-resolved spectrometer disclosed in this embodiment includes a pump light and a detection light. The spectrometer includes a light source module, a beam splitter, a modulator 1, a modulator 2, an amplifier 1, an amplifier 2, a pump light generating module, a detection light generating module, a delay module, a sample chamber and a data acquisition module. The light source module generates laser light of a specified wavelength, and a femtosecond laser system or a picosecond laser system can be used, including an oscillator and an amplifier; the beam splitter is arranged after the light source, and splits the laser light output by the light source into two beams, and a fiber beam splitter, a beam splitter or other beam splitting optical element can be used. Modulator 1 and modulator 2 are respectively arranged on two paths after beam splitting, and control the light at different times, also known as seed light, to be injected into the amplifier module behind, which can achieve different laser repetition frequencies. The modulator is an acousto-optic modulator or an electro-optic modulator; Amplifier 1 and amplifier 2 are respectively arranged after modulator 1 and modulator 2, and are used to amplify the input seed light to achieve high-power laser pulses. The amplifier can be a fiber amplifier, a regenerative amplifier or a disk laser amplifier; The pump light generation module is arranged after amplifier 1, and is used to optically process the laser and output the required pump light. The pump light can be the light directly output by the amplifier, or can be an optically pumped nonlinear crystal output by the amplifier, such as LiB3O5, β-BaB2O4, LiNbO3 and other crystals, or can be a wavelength tunable laser output by an optical parametric amplifier pumped by the amplifier, or can be a supercontinuum white light or other light bands generated by the optically pumped material output by the amplifier; The detection light generation module is arranged after another amplifier module, and is used to optically process the laser and output the required detection light signal. The detection light signal can be the light directly output by the amplifier, or can be an optically pumped nonlinear crystal output by the amplifier, such as LiB3O5, Crystals such as β-BaB2O4, LiNbO3, etc. can be amplifiers pumping an optical parametric amplifier to output a wavelength-tunable laser, or can be the optical pumping material output by the amplifier to generate supercontinuum white light or other light in other wavelength bands; the delay module includes an optical delay module and an electronic delay module. The optical delay module can be set at any position between modulator 1 and the sample in the pump light path, or at any position between modulator 2 and the sample in the detection light path. By changing the optical path difference between the pump light and the detection light reaching the sample, the delay is generated and controlled, which can generally be from tens of attoseconds to tens of nanoseconds. The electronic delay module can trigger the modulator modules of the pump light and the detection light by electronic methods, realize the selection of seed light injection into the amplifier at different times, realize the control of the time difference between the pump light and the detection light reaching the sample, and realize the delay control from nanoseconds to milliseconds. The electronic delay module can be a pulse delay generator circuit. For example, if you only need to measure the transient absorption spectrum within tens of nanoseconds, you only need to fix the electronic delay module for synchronization and control the delay through the optical delay module. If you need to measure a process on a larger time scale, enable both the optical delay module and the electronic delay module.Taking the repetition frequency of the light source module as 80MHz as an example, the time difference between the two nearest seed lights is 12.5 nanoseconds. Taking the seed light of the pump light as the benchmark, the modulator module of the detection light is triggered by electronic delay, and different seed light injections are selected to achieve a minimum interval of 12.5 nanoseconds and a maximum interval of 100 microseconds or a time difference of 10 milliseconds. The final time difference is the delay of the optical delay module and the electronic delay module, which realizes the delay generation and control from tens of attoseconds to milliseconds; the sample chamber is used to place the sample to be tested. After the pump light passes through the sample, the sample is excited from the ground state to the excited state. The detection light passes through the sample again and then enters the detector; the data acquisition module collects one or more of the voltage, current, photon count, photoelectron count, and spectral signal output by the spectrometer under different delays through the control of the delay module, and records the data.

[0025] Example 2

[0026] like Figure 2 As shown, the multi-scale time-resolved spectrometer disclosed in this embodiment has two detection light modules and two optical delay modules. The detection light is composed of detection light 1 and detection light 2. The detection light 1 is arranged after the amplifier 2. The detection light 1 can be a narrow linewidth laser generation module. The detection light 2 is arranged after the amplifier 3 for generating a narrow pulse laser.

[0027] The delay module includes an optical delay module and an electronic delay module. The optical delay module includes two optical delay modules: the first optical delay module 1 is set at any position between the modulator and the sample in the optical path of the pump light, and generates and controls the delay by changing the optical path difference between the pump light and the two detection lights, which can generally be from tens of attoseconds to tens of nanoseconds; the second optical delay module 2 is set at any position between the modulator and the sample in any optical path of the detection light 1 generation module and the detection light 2 generation module, and realizes the delay between the two by changing the optical path difference between the detection light 1 and the detection light 2 to reach the sample, so as to ensure the signal generation process on the sample. The electronic delay module can trigger the modulator modules of the pump light and the two detection lights by electronic methods, select the seed light at different times to inject into the amplifier, and realize synchronization. The electronic delay module can be a pulse delay generator circuit. If it is necessary to measure the time-resolved absorption / reflection spectrum within tens of nanoseconds, as long as the electronic delay module is fixed and synchronized, the optical delay module 2 is used to control the detection light 1 generation module and the detection light 2 module to generate signals, and the optical delay module 1 is used to realize the delay of the pump and detection light. If it is necessary to measure a process with a larger time scale, the optical delay module and the electronic delay module are enabled at the same time. Taking the repetition frequency of the light source module as 80MHz as an example, the time difference between the two nearest seed lights is 12.5 nanoseconds. Taking the seed light of the pump light as the benchmark, the modulator module of the detection light is triggered by the electronic delay, and different seed lights are selected for injection, so that the minimum interval of 12.5 nanoseconds and the maximum interval of 100 microseconds or 10 milliseconds can be achieved. The final time difference is the delay of the optical delay module and the electronic delay module, which realizes the delay generation and control from tens of attoseconds to milliseconds.

[0028] Example 3

[0029] like Figure 3 As shown, the difference between the multi-scale time-resolved spectrometer disclosed in this embodiment and embodiment 2 is that the two-path detection light is composed of an amplifier module, a detection light 1 module and a detection light 2 module, which can save a modulator and an amplifier, and the optical path is simpler.

[0030] Example 4

[0031] like Figure 4 As shown, this embodiment discloses a multi-scale time-resolved spectrometer with two pump lights and one detection light. The difference from Embodiment 2 is that two of the three amplifiers are followed by pump light 1 and pump light 2 modules.

[0032] Example 5

[0033] like Figure 5As shown, this embodiment discloses a multi-scale time-resolved spectrometer with two pump lights and one detection light. The difference from Example 4 is that the two pump lights are composed of an amplifier module, a pump light 1 module and a pump light 2 module, which can save one modulator and an amplifier, and the optical path is simpler.

[0034] Example 6

[0035] like Figure 6 As shown, this embodiment discloses a multi-scale time-resolved spectrometer with two pumping lights and two detection lights. Compared with Embodiment 2, it has an additional amplifier, a pumping light module and an optical delay module.

[0036] The delay module includes an optical delay module and an electronic delay module, and the optical delay module includes three optical delay modules: the first optical delay module 1 is set at any position between the modulator and the sample in the optical path of the pump light 1 generating module, and the second optical delay module 2 is set at any position between the modulator and the sample in the optical path of the pump light 2 generating module. By changing the optical delay 1 and the optical delay 2, the delay between the two pump lights is generated and controlled, and the delay between the two pump lights and the two detection lights is generated and controlled at the same time. The third optical delay module 3 is set at any position between the modulator and the sample in the optical path of the detection light 1 generating module, and the delay between the two detection lights is generated and controlled. The three optical delay modules can also be one in the pump light path and two in the detection light path, respectively realizing the delay between the two pump lights, between the two detection lights, and between the pump light and the detection light. The function of the electronic delay module is similar to that in Example 2.

[0037] Example 7

[0038] like Figure 7 As shown, this embodiment discloses a multi-scale time-resolved spectrometer with two pump lights and two detection lights. Compared with Example 6, four amplifier modules are changed to three amplifier modules, and two pump light modules are connected to the amplifier 1 module; the optical delay 1 can be placed between the modulator 1 and the amplifier 1 or between the amplifier 1 and the two pump lights in the pump light path, which can save one amplifier module and make the optical path simpler.

[0039] Example 8

[0040] like Figure 8 As shown, this embodiment discloses a multi-scale time-resolved spectrometer with two pump lights and two detection lights. Compared with Example 6, four amplifier modules are changed to three amplifier modules, and two detection light modules are connected to the amplifier 3 module; the optical delay 2 can be placed between the modulator 3 and the amplifier 3 or between the amplifier 3 and the two detection lights in the detection light path, which can save one amplifier module and make the optical path simpler.

[0041] Example 9

[0042] like Fig. 9 As shown, the present embodiment discloses a multi-scale time-resolved spectrometer with two pump lights and two detection lights. Compared with Example 6, four amplifier modules are changed to two amplifier modules, and each amplifier module is connected to two pump light modules or two detection light modules, which can save two amplifier modules, and the optical path is simpler. The optical delay 1 can be placed in the pump light path or the detection light path between the modulator and the amplifier or between the amplifier and the two pump lights or the two detection lights.

Claims

1. A multi-scale time-resolved spectrometer, characterized in that: The invention comprises a light source module and a sample chamber. A beam splitter, a modulator, an amplifier and a light generating module are sequentially arranged on the optical path from the light source module to the sample chamber. The light generating module comprises a pump light generating module and a detection light generating module. An optical delay module is arranged on the optical path from the modulator to the pump light generating module or the detection light generating module. An electronic delay module is arranged between the light source module and the modulator. After the light source module generates laser, the light is split by a beam splitter. The light split into multiple beams is processed by a modulator to form seed lights with different repetition frequencies respectively. The seed lights with different repetition frequencies are amplified by amplifiers to form multi-channel laser pulses. The multi-channel laser pulses output corresponding optical signals respectively through the pump light generating module and the detection light generating module. The modulators of the pump light and the detection light are triggered by the electronic delay module to realize the injection of seed lights into the amplifier at different times. The optical path difference between the pump light and the detection light reaching the sample is changed in combination with the optical delay module to realize the control of the time difference between the pump light and the detection light reaching the sample.

2. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: It also includes a detector and a data acquisition module, wherein the detector receives the detection light passing through the sample, and the data acquisition module is connected to the detector signal to collect at least one of the voltage, current, photon count, photoelectron count output by the detector under different delays, and the spectral signal output by the spectrometer.

3. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The modulator includes a pump optical path modulator and a detection optical path modulator, and the amplifier includes a pump optical path amplifier and a detection optical path amplifier.

4. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The light source module is a femtosecond laser or a picosecond laser.

5. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The modulator is an acousto-optic modulator or an electro-optic modulator.

6. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The amplifier is a fiber amplifier, a regenerative amplifier or a disk laser amplifier.

7. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The beam splitter is at least one of a fiber beam splitter and a beam splitter.

8. The multi-scale time-resolved spectrometer according to claim 1, characterized in that: The electronic delay module is a pulse delay generator circuit.

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