Angle resolution photoelectron spectroscopy device and measuring method thereof

Abstract

The invention provides an angle resolution photoelectron spectroscopy device and a measurement method thereof. The angle-resolved photoelectron spectroscopy device comprises a laser module, a higher harmonic module, a pump light module, a higher harmonic focusing and light path switching module and an analyzer angle-resolved photoelectron spectroscopy system module. Based on an extreme ultraviolet band higher harmonic light source, through a pumping detection technology and through light path switching, the device is combined with a hemispherical analyzer angle-resolved photoelectron spectroscopy and a flight time type angle-resolved photoelectron spectroscopy, the multifunctional time-resolved and angle-resolved photoelectron spectroscopy measurement function is achieved, and the purposes that the time resolution is smaller than 200 fs, the energy resolution is smaller than 50 meV, and the time resolution is smaller than 200 fs and the energy resolution is smaller than 50 meV are achieved. The method is used for research of non-equilibrium phase change and dynamic evolution processes in condensed substance quantum materials such as a high-temperature superconducting system, an exciton insulator topological material and a charge density wave material. According to the invention, the test of the dynamic range of a higher electronic structure is realized, and the method has important application value in the research of condensed substances and quantum materials.

Description

Technical Field

[0001] The invention belongs to the field of combining ultrafast phenomena with condensed matter physics, and specifically relates to an angle-resolved photoelectron energy spectrum device and a measurement method thereof. Background Art

[0002] A major challenge in current condensed matter physics is how to understand the physical mechanisms that determine the important properties of complex materials, and use the physical understanding of these existing materials to provide important guidance for finding new materials. Of particular interest are quantum materials, that is, materials that cannot be described by single-electron band structures, such as strongly correlated systems, low-dimensional nanomaterials, topological insulators, valley electrons, heavy fermions, charge density wave materials, etc. These materials have novel physical properties, such as high-temperature superconductivity and colossal magnetoresistance, which have broad application prospects. However, since the degrees of freedom such as lattice, charge, spin and orbit in these systems are closely related, how to separate the role of each degree of freedom and find the physical laws that play a decisive role has become a major challenge in today's physics and materials science.

[0003] Angle Resolved Photoemission Spectroscopy (ARPES) is the most intuitive means to study the band structure of materials. After 20 years of continuous development, its momentum and energy resolution has been continuously improved, providing the most powerful means for people to explore some very important physical phenomena in high-temperature superconductors. By measuring the kinetic energy and momentum of photoelectrons generated by the photoelectric effect with ultra-high resolution, people can obtain the kinetic energy and momentum information of excitons inside solids. In the study of copper oxide high-temperature superconductors, ARPES plays a key role in revealing the symmetry of the superconducting energy gap, the pseudogap of the non-superconducting state, and the electron-phonon interaction. However, due to the close correlation of various elementary excitations in quantum material systems, how to separate the key factors that determine the physical properties is still a severe scientific challenge. Extending ARPES to the ultrafast time scale (10-15 seconds to femtoseconds, or even attoseconds 10-18 seconds) will enable technicians in this field to further detect the dynamic information of electrons, and is expected to separate various excitations on different time scales, providing a new window for studying these quantum materials. The ultrafast time-resolved angle-resolved photoelectron spectrometer can take a "movie" of the electron energy spectrum during the phase transition process, obtain multi-dimensional information such as energy, momentum and time of electrons in different momentum spaces, and directly reveal the formation process of superconducting electron Cooper pairs. This information will provide important information for revealing the insulator-superconductor phase transition in the material, and provide a direct experimental basis for ultimately solving the high-temperature superconductivity mechanism.

[0004] By using the high-order harmonics (HHG) generated by the interaction between ultrashort intense laser pulses and inert gases, a coherent EUV light source can be obtained, whose photon energy ranges from 20 to 100 eV and whose pulse width can range from tens of femtoseconds to tens of attoseconds, making it an ideal tool for measuring and regulating extremely ultrafast processes such as electron dynamics behavior. By combining a high-order harmonic source with an angle-resolved electron spectrometer with momentum and energy resolution capabilities, the ultrafast time-resolved ARPES measurement technology can be realized, which can obtain the ability to measure the dynamic information of the kinetic energy and momentum of excitons inside solids, and through the time-resolved measurement of some band structures around the Fermi level in the strongly correlated system materials that people are concerned about, an in-depth study of superconducting phenomena can be achieved.

[0005] Although with the increasing maturity of ARPES technology, its energy resolution can be less than 1meV, the time-resolved ARPES system developed in combination with ultrashort pulse lasers cannot achieve high energy resolution and time resolution at the same time. This is because high energy resolution requires a narrow linewidth laser, and the pulse width corresponding to a narrow linewidth laser is very long. As a compromise, a pulse width of about 100fs and an energy resolution of about 100meV can be achieved on a time-resolved ARPES system. Another factor that restricts energy resolution is the space charge effect. Since the energy of photons in the EUV band is very high, it is easy to produce a space charge effect when the laser interacts with the sample. To this end, the intensity of the laser must be reduced. The best way is to increase the repetition frequency to reduce the energy of a single pulse. It is generally believed that a repetition frequency of more than 100kHz is more appropriate.

[0006] There are two types of analyzers in the ARPES system: one is a hemispherical energy analyzer, and the other is an energy analyzer based on time-of-light (TOF). The hemispherical analyzer uses a slit for selective filtering and can only detect photoelectrons with characteristic flight directions that pass through the slit. Therefore, one measurement can only detect one line in the two-dimensional momentum space. To measure a complete Fermi surface, it is necessary to continuously rotate the sample angle or the electric field deflection for multiple measurements, and then interpolate the measurement results to obtain a complete three-dimensional energy-momentum spectrum. This has a very low acquisition efficiency, takes a long time to collect data, and cannot guarantee that the sample state and the photoelectron emission position remain unchanged during the measurement process, and whether they are consistent with the state of the laser. The shape of the sample Fermi surface obtained by the interpolation method may be different from the actual shape, especially when there are many Fermi bands. In addition, since the hemispherical analyzer does not directly measure the electronic signal, it requires a strong laser power. When the laser power is high, due to nonlinear effects and space charge effects, the obtained electronic signal intensity and the number of photoelectrons show a nonlinear growth trend, which affects the reliability of the data. The TOF energy analyzer detects the energy and angle information of electrons through the flight time of photoelectrons and delay line detectors. Since there is no slit, it can simultaneously detect a plane in momentum space to directly obtain a three-dimensional EK spectrum. Since the sample angle does not need to be changed, the accuracy of the data is improved, and the data collection efficiency is also improved. In addition, due to the reduction of the required laser power threshold and direct detection of photoelectrons, the detection efficiency and linearity are greatly improved, which is very suitable for combining with high repetition rate and low energy ultrashort pulse lasers to achieve time-resolved ARPES.

[0007] However, there is no device that combines the hemispherical analyzer and the TOF analyzer. Combining the two in one device will give full play to their respective advantages and be more conducive to achieving high time resolution and high energy resolution angle-resolved photoelectron spectroscopy measurements, and applying them to the measurement of the electronic energy level structure dynamics of condensed matter. Summary of the invention

[0008] Therefore, the purpose of the present invention is to overcome the defects in the prior art and provide an angle-resolved photoelectron spectroscopy device and a measurement method thereof. The angle-resolved photoelectron spectrometer based on extreme ultraviolet band high-order harmonics combined with a hemispherical analyzer and a time-of-flight analyzer of the present invention realizes high-time-resolution and high-energy-resolution angle-resolved photoelectron spectroscopy measurement and is applied to the measurement of the electronic energy level structure dynamics of condensed matter.

[0009] The present invention combines the advantages of a hemispherical analyzer and a TOF analyzer, combines the two detectors, and shares a high-order harmonic light source, respectively realizing high-energy resolution and high-time resolution angular-resolved photoelectron energy spectrum measurements. According to different sample requirements, the inventor can switch to select the ARPES of the hemispherical analyzer and / or the TOF analyzer to realize multifunctional measurement, provide important information for revealing the insulator-superconductor phase transition in the material, and provide a direct experimental basis for ultimately solving the high-temperature superconductivity mechanism, and also realize higher time resolution and energy resolution measurement capabilities to meet the growing needs of scientific research users.

[0010] Before describing the present invention, the terms used in this article are defined as follows:

[0011] The term "ARPES" ​​means: Angle Resolved Photoemission Spectroscopy.

[0012] The term "TOF" means: time of flight, the English name is time-of-light.

[0013] The term "XUV" refers to extreme ultraviolet, and the wavelength range is usually 10 to 124 eV.

[0014] To achieve the above object, a first aspect of the present invention provides an angle-resolved photoelectron spectroscopy device, the angle-resolved photoelectron spectroscopy device comprising:

[0015] A laser module for generating femtosecond laser light;

[0016] A high-order harmonics module for generating and extracting single-order high-order harmonics;

[0017] Pump light module for generating high-order harmonics;

[0018] A high-order harmonic focusing and optical path switching module for focusing the high-order harmonics onto the sample to be tested and realizing the switching of the high-order harmonics on the optical path; and

[0019] An analyzer angle-resolved photoelectron spectroscopy system module for collecting photoelectric signals emitted by the sample to be tested;

[0020] in:

[0021] The analyzer angle-resolved photoelectron energy spectrum system module comprises: a hemispherical analyzer angle-resolved photoelectron energy spectrum system module and a time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

[0022] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention, the laser module comprises a femtosecond laser and a femtosecond beam splitter, the femtosecond laser emits a femtosecond laser which is split into two laser beams by the femtosecond beam splitter;

[0023] The average power of the femtosecond laser is greater than 100 W, preferably greater than 150 W, more preferably greater than 200 W; and / or

[0024] The pulse width of the femtosecond laser is 30 to 200 fs, preferably 30 to 150 fs, and more preferably 30 to 70 fs.

[0025] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention, the high-order harmonic module comprises:

[0026] High harmonic generation vacuum chamber;

[0027] High-order harmonic switching vacuum cavity;

[0028] a monochromator vacuum chamber; and

[0029] High-order harmonic light spot and energy measurement vacuum cavity;

[0030] Preferably, the laser module, the high-order harmonic generation vacuum cavity, the high-order harmonic switching vacuum cavity, the monochromator vacuum cavity, the high-order harmonic light spot and the energy measurement vacuum cavity are arranged on the same horizontal axis; wherein,

[0031] The high-order harmonic generation vacuum chamber comprises: a gas target, a high-order harmonic generation cavity reflector and a concave reflector;

[0032] The high-order harmonic switching vacuum chamber comprises a switching perforated mirror, a metal filter, an extreme ultraviolet band reflector and a spectrometer, and the spectrometer is preferably an XUV spectrometer;

[0033] The monochromator vacuum chamber comprises: a monochromator tire mirror, a grating and a slit; and / or

[0034] The high-order harmonic light spot and energy measurement vacuum chamber comprises a photodiode and a photodiode electric translation stage.

[0035] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention,

[0036] In the high-order harmonic generation vacuum cavity: the femtosecond laser generated by the laser module is focused onto the gas target by the concave reflector after mode matching, and the gas target sprays an inert gas to interact with the femtosecond laser to generate high-order harmonics in the extreme ultraviolet band, which enter the high-order harmonic switching vacuum cavity after passing through the high-order harmonic generation cavity reflector; the extreme ultraviolet band is preferably 16 to 60 eV, more preferably 16 to 55 eV, and further preferably 16 to 50 eV;

[0037] In the high-order harmonic switching vacuum cavity: the high-order harmonic is coaxially transmitted with the femtosecond laser, and is guided out of the high-order harmonic switching vacuum cavity through the switching mirror with holes and the metal filter in sequence; the high-order harmonic passes through the small hole of the switching mirror with holes and is filtered out of the femtosecond laser by the metal filter, and is guided into the spectrometer through the extreme ultraviolet band reflector and / or is linearly propagated into the monochromator vacuum cavity;

[0038] In the monochromator vacuum cavity: the high-order harmonics entering the monochromator vacuum cavity are collimated by the one monochromator tire mirror and then enter the grating for dispersion, the dispersed light spots are spatially separated according to the wavelength, and after being collimated by another monochromator tire mirror, a single-order narrow-band spectrum is extracted by the slit and enters the high-order harmonic light spot and energy measurement vacuum cavity; and / or

[0039] In the high-order harmonic light spot and energy measurement vacuum chamber: the photodiode is located on the photodiode electric translation stage to measure the power of the high-order harmonics of the single-order narrow-band spectrum;

[0040] Preferably, the high-order harmonic switching vacuum chamber further comprises: a switching mirror frame and a switching vacuum chamber electric translation stage, the extreme ultraviolet band reflector and the switching mirror frame are jointly arranged on the switching vacuum chamber electric translation stage; and / or

[0041] Preferably, the monochromator vacuum chamber further comprises: a slit electric translation stage, a monochromator vacuum electric translation stage and a monochromator vacuum rotating stage, the slit is located on the slit electric translation stage, and the grating is located on the monochromator vacuum electric translation stage and the monochromator vacuum rotating stage.

[0042] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention, the pump light module comprises:

[0043] Pump reflector;

[0044] A pump light delay adjustment vacuum cavity for adjusting the delay between the pump light and the high-order harmonics; and

[0045] A pump light guiding cavity for guiding the pump light into the high-order harmonic focusing and optical path switching module;

[0046] Preferably, the pump light delay adjustment vacuum chamber comprises: a delay adjustment reflector, a delay adjustment mirror frame and a delay adjustment electric translation stage.

[0047] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention, the high-order harmonic focusing and optical path switching module comprises: a focusing tire mirror and a focusing electric translation stage; wherein,

[0048] The single-order narrow-band spectrum high harmonics selected by the monochromator in the monochromator vacuum chamber are focused by the focusing tire mirror onto the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module to obtain an angle-resolved photoelectron energy spectrum; and / or

[0049] The single-order narrow-band spectrum high harmonics selected by the monochromator in the monochromator vacuum cavity are focused by the focusing tire mirror, overlapped with the pump light in space, and focused together on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module;

[0050] Preferably, the focusing tire mirror is mounted on the focusing electric translation stage, and the switching of high-order harmonics on the optical path is achieved by moving the focusing electric translation stage; and / or

[0051] Preferably, the high-order harmonic focusing and optical path switching module further comprises: a focusing perforated mirror, a focusing reflector and a focusing beam splitter.

[0052] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention, the angle-resolved photoelectron spectroscopy device comprises: a high-order harmonic introduction vacuum cavity;

[0053] The high-order harmonic introduction vacuum chamber is equipped with an introduction reflector of an electric mirror holder; and / or

[0054] The high-order harmonic introduction vacuum chamber introduces the high-order harmonics output by the high-order harmonic focusing and optical path switching module into the hemispherical analyzer angle-resolved photoelectron spectroscopy system module and / or the time-of-flight analyzer angle-resolved photoelectron spectroscopy system module.

[0055] According to the angle-resolved photoelectron spectroscopy device of the first aspect of the present invention,

[0056] The hemispherical analyzer angle-resolved photoelectron energy spectrum system module collects the photoelectron signal emitted by the sample to be tested to obtain an angle-resolved photoelectron energy spectrum, and obtains a time-resolved angle-resolved photoelectron energy spectrum by changing the time delay between the pump light and the high-order harmonics; and / or

[0057] The time-of-flight analyzer angle-resolved photoelectron energy spectrum system module collects photoelectron signals emitted by the sample to be tested, measures the flight time and the emission angle to obtain the angle-resolved photoelectron energy spectrum, and obtains the time-resolved angle-resolved photoelectron energy spectrum by changing the time delay between the pump light and the higher harmonics.

[0058] The second aspect of the present invention provides a method for measuring angle-resolved photoelectron spectroscopy, wherein the method uses the angle-resolved photoelectron spectroscopy device described in the first aspect to measure angle-resolved photoelectron spectroscopy;

[0059] Preferably, the measuring method comprises the steps of:

[0060] The laser module generates femtosecond laser and divides it into two paths. One path of laser light enters the high-order harmonic module and the high-order harmonic focusing and optical path switching module in sequence, and is respectively focused on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; the other path of laser light enters the pump light delay adjustment vacuum cavity, the pump light guide cavity and the high-order harmonic focusing and optical path switching module in sequence, overlaps with the high-order harmonic beam line in space, and is jointly focused on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

[0061] The second aspect of the present invention provides a method for measuring angle-resolved photoelectron spectroscopy, wherein the method uses the angle-resolved photoelectron spectroscopy device described in the first aspect to measure angle-resolved photoelectron spectroscopy;

[0062] Preferably, the measuring method comprises the steps of:

[0063] The femtosecond laser emits a femtosecond laser, which is divided into two laser paths through the femtosecond beam splitter. One laser path enters the high-order harmonic generation vacuum cavity, the high-order harmonic switching vacuum cavity, the monochromator vacuum cavity, and the high-order harmonic light spot and energy measurement vacuum cavity in sequence to obtain the high-order harmonics of the single-order narrow-band spectrum, enters the high-order harmonic focusing and optical path switching module, and is focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; the other laser path enters the pump reflector, the pump light delay adjustment vacuum cavity, and the pump light guide cavity in sequence, enters the high-order harmonic focusing and optical path switching module, overlaps with the high-order harmonics of the single-order narrow-band spectrum in space, and is jointly focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

[0064] The present invention shares a beam of high-order harmonic light source, which can be switched to provide to a hemispherical analyzer ARPES and a TOF-type ARPES, combining the advantages of the hemispherical analyzer ARPES and the TOF-type ARPES, and realizing the measurement function of an angle-resolved photoelectron energy spectrum with both high time resolution and high energy resolution. The final invention is a time-resolved ARPES device. According to different sample requirements, we can switch and select the hemispherical analyzer and the TOF analyzer ARPES to realize multifunctional photoelectron energy spectrum measurement.

[0065] According to a preferred embodiment of the present invention, the time-resolved ARPES device of the present invention comprises a high-power femtosecond laser, a high-order harmonic generation cavity, a monochromator, a high-order harmonic switching and focusing cavity, a hemispherical analyzer ARPES, a TOF analyzer ARPES, and an XUV flat-focus field spectrum;

[0066] The high-power femtosecond laser is used to generate femtosecond laser in the 1 μm band, with a typical average power greater than 100 W, a pulse width of 60 fs, and a repetition frequency of 1 MHz;

[0067] The high-order harmonic generation cavity is used to introduce high-power femtosecond laser into the cavity to interact with the inert gas target to generate harmonics in the extreme ultraviolet band, wherein the typical harmonics are odd harmonics with orders ranging from 15 to 49 and a band ranging from 16 to 60 eV;

[0068] The monochromator is used for selecting high-order harmonic single-order narrow-band spectrum, and can extract a narrow-band spectrum component, and is composed of a monochromator tire mirror, a grating, and a slit;

[0069] Monochromator tire mirror: used to collimate the generated high-order harmonics;

[0070] Grating: used for high-order harmonic dispersion;

[0071] Slit: used to select a narrowband spectrum;

[0072] The high-order harmonic switching and focusing cavity is used to focus the narrow-band light source selected by the monochromator onto the sample through a focusing tire mirror, and switch to two ARPES, which consists of two focusing tire mirrors and a focusing electric translation stage;

[0073] Focusing tire mirror: used to focus narrow-band light source onto the sample;

[0074] Focusing motorized translation stage: used to switch the light source to the two ARPES;

[0075] The hemispherical analyzer ARPES is used for collecting photoelectron signals;

[0076] The TOF analyzer ARPES is used for collecting photoelectron signals;

[0077] The XUV flat-focus field spectrum is used to measure the high-order harmonic spectrum distribution;

[0078] The high-power femtosecond laser, high-order harmonic generation cavity, monochromator, high-order harmonic switching and focusing cavity, hemispherical analyzer ARPES, TOF analyzer ARPES, and XUV flat-focus field spectrum are placed on the same horizontal axis;

[0079] The pump light delay adjustment vacuum chamber comprises: 4 delay adjustment mirrors and a delay adjustment mirror frame, wherein 2 delay adjustment mirrors are mounted on a delay adjustment electric translation stage;

[0080] The high-order harmonic focusing and optical path switching module comprises: a focusing electric translation stage and two focusing tire mirrors, wherein the two focusing tire mirrors are mounted on the focusing electric translation stage.

[0081] High-power femtosecond laser, high-order harmonic generation cavity, monochromator, high-order harmonic focusing and switching cavity, hemispherical analyzer ARPES, and TOF ARPES are arranged in sequence according to the laser propagation direction;

[0082] The femtosecond laser outputs high-power and high-repetition-rate femtosecond laser, which is introduced into the high-order harmonic generation cavity through multiple mirrors, and then focused into the gas target by a concave mirror, and interacts with the gas to produce a high-order harmonic beam line. The high-order harmonic beam line is injected into the grating of the monochromator, and the dispersed light spot is selected by the slit to produce a narrow-band spectrum, which is focused onto the sample by the focusing tire mirror to ionize photoelectrons. The focusing tire mirror is mounted on the focusing electric translation stage. By moving the focusing electric translation stage, the high-order harmonic beam can be switched to the hemispherical analyzer and the TOF analyzer for electron energy spectrum signal collection. After analysis, information such as the sample energy level structure can be obtained.

[0083] The time-resolved ARPES device uses a high-order harmonic light source in the extreme ultraviolet band, and uses femtosecond pump-high-order harmonic detection to achieve the measurement of time-resolved angle-resolved photoelectron energy spectrum. Due to the high energy of high-order harmonic photons, electrons outside the Brillouin zone of most materials can be ionized to achieve the detection of deeper energy level structures, and provide experimental basis for the study of quantum materials, especially superconducting mechanisms. The present invention combines the advantages of the hemispherical analyzer and the TOF analyzer, uses the same high-order harmonic light source, can be automatically switched, and realizes a multifunctional time-resolved ARPES device, which has important application value in quantum materials, especially superconductors, topological insulators, density waves and other materials.

[0084] According to another preferred embodiment of the present invention, the time-resolved ARPES device of the present invention comprises a high-power femtosecond laser, a high-order harmonic generation cavity, a high-order harmonic switching cavity, a monochromator, a slit, a high-order harmonic spot and energy measurement, a high-order harmonic focusing and switching cavity, a hemispherical analyzer ARPES system, a high-order harmonic light guide, a TOF analyzer ARPES system, a pump light delay system, a pump light light guide cavity, and an XUV spectrometer, which are sequentially arranged according to the laser propagation direction;

[0085] The high-power femtosecond laser is used to generate femtosecond laser, which enters the high-order harmonic generation cavity to interact with the inert gas to generate high-order harmonics, and the high-order harmonics enter the monochromator to select a narrow-band spectrum; a small part of the main laser is separated as pump light, which is respectively passed through the pump light delay system and the pump light guide cavity to enter the high-order harmonic focusing and switching vacuum cavity, and the high-order harmonics are focused by the focusing tire mirror and combined with the pump light, and are respectively controlled by the electric switch to enter the hemispherical analyzer ARPES system and the TOF analyzer ARPES system samples, and the time-resolved and angle-resolved photoelectron energy spectrum measurement functions are realized by changing the pump light and the high-order harmonic delay;

[0086] A gas target is installed in the high-order harmonic generating cavity, and an inert gas is sprayed out from the gas target and interacts with the incident high-power femtosecond laser to generate high-order harmonics. The high-order harmonic beam line is coaxially transmitted with the femtosecond laser, and a metal film is installed on the transmission path to block the femtosecond laser and extract the high-order harmonics.

[0087] The high-power femtosecond laser is a laser with a central wavelength of 1030nm, which is used to output femtosecond pulse laser, with an average output power of more than 200W and a repetition frequency of 1MHz.

[0088] The high-order harmonic generation cavity is a vacuum cavity in which the femtosecond laser output by a high-power femtosecond laser is transmitted and interacts with gas, and is used to generate high-order harmonics. The typical spectrum range of high-order harmonics is from 16 to 50 eV. A gas valve, multiple reflectors, concave reflectors, metal filters, etc. are installed in the high-order harmonic generation cavity;

[0089] The high-order harmonic switching cavity generates high-order harmonics that are coaxially transmitted with the femtosecond laser, and uses a switching mirror with holes to guide the femtosecond laser out of the cavity. The high-order harmonics pass through the small holes and are filtered out by a metal film to remove the femtosecond laser, and are then guided into an XUV spectrometer by a reflector for spectral measurement.

[0090] The monochromator collimates the high-order harmonics and disperses them through a grating. The dispersed light spots are spatially separated according to the wavelengths. The narrow-band spectrum of the corresponding band is extracted by the slit, and the high-order harmonic light spots and energy are measured. The monochromator is composed of two monochromator tire mirrors, a grating, a slit, a vacuum electric translation stage of the monochromator in vacuum, and a monochromator rotating stage.

[0091] The high-power femtosecond laser, high-order harmonic generation vacuum cavity, high-order harmonic switching cavity, monochromator, slit, high-order harmonic spot and energy measurement are arranged on the same horizontal axis;

[0092] The high-order harmonic focusing and electric switching vacuum chamber is used to install two focusing tire mirrors, which are used to focus high-order harmonics on the sample. The two focusing tire mirrors are installed on a focusing electric translation stage, and the high-order harmonics are switched on the optical path by focusing and moving the translation stage, and are respectively introduced into the hemispherical analyzer ARPES and the TOF analyzer ARPES;

[0093] Figure 1 The hemispherical analyzer ARPES is used to collect the photoelectron signal emitted by the sample and obtain the angle-resolved photoelectron energy spectrum, and the time-resolved angle-resolved photoelectron energy spectrum is obtained by changing the time delay between pumping and detection;

[0094] The TOF analyzer ARPES is used to collect the photoelectron signal emitted by the sample, obtain the angle-resolved photoelectron energy spectrum by measuring the flight time and the emission angle, and obtain the time-resolved angle-resolved photoelectron energy spectrum by changing the time delay between pumping and detection;

[0095] The spectrometer is used to measure the high-order harmonic spectrum distribution;

[0096] The delay adjustment vacuum chamber is equipped with a precision delay adjustment electric translation stage for adjusting the delay between the pump light and the higher harmonics, thereby realizing the precision delay measurement function of pumping and detection;

[0097] The slit vacuum chamber is equipped with a slit and a slit electric translation stage, which can accurately control the slit width and slit position, and is used to cooperate with a monochromator to realize the selection of a narrow-band high-order harmonic light source;

[0098] The high-order harmonic power measurement vacuum chamber is equipped with an extreme ultraviolet light-sensitive photodiode and a photodiode electric translation stage for measuring the selected high-order harmonic power;

[0099] The high-order harmonics are introduced into the vacuum chamber, and an extreme ultraviolet band reflector of a two-dimensional electric mirror frame is installed to introduce the high-order harmonics into the TOF analyzer ARPES to avoid interference between the TOF analyzer ARPES and the hemispherical analyzer ARPES;

[0100] The high-order harmonic switching vacuum cavity is equipped with an ultraviolet band reflector, an ultraviolet band mirror frame and an ultraviolet band electric translation stage, which are used to introduce high-order harmonics into the spectrometer for spectral distribution measurement. The position of the ultraviolet band reflector is controlled by the ultraviolet band electric translation stage. When withdrawn from the optical path, the high-order harmonics propagate linearly to the monochromator vacuum cavity;

[0101] The high-power femtosecond lasers arranged in sequence according to the laser propagation direction are divided into two paths. One path enters the high-order harmonic generation vacuum cavity, the high-order harmonic switching vacuum cavity, the monochromator vacuum cavity, the slit vacuum cavity, the high-order harmonic power measurement vacuum cavity, the high-order harmonic focusing and switching vacuum cavity, the hemispherical analyzer ARPES, the high-order harmonic introduction vacuum cavity, and the TOF analyzer ARPES; the other path enters the time-delay vacuum cavity, the 45-degree reflection vacuum cavity, the high-order harmonic focusing and switching vacuum cavity, the hemispherical analyzer ARPES, the high-order harmonic introduction vacuum cavity, and the TOF analyzer ARPES.

[0102] A high-power femtosecond laser generates femtosecond laser, which is divided into two paths. One path is used as the detection light, and enters the high-order harmonic generation vacuum chamber to interact with the inert gas target to generate high-order harmonics. The generated high-order harmonics can be arbitrarily introduced into the spectrometer to measure the spectral distribution through the optical path switching vacuum chamber, or can be linearly propagated to the monochromator vacuum chamber and the slit vacuum chamber for the selection of narrow-band spectrum light source, and then enter the high-order harmonic focusing and switching vacuum chamber to be focused on the hemispherical analyzer ARPES and TOF analyzer ARPES for angle-resolved photoelectron energy spectrum measurement; the other path is used as the pump light, and enters the delay vacuum chamber, the 45-degree reflection vacuum chamber, the high-order harmonic focusing and switching vacuum chamber, and overlaps with the high-order harmonic beam line in space, and is focused on the ARPES sample together. By changing the delay, the measurement functions of time-resolved and angle-resolved photoelectron energy spectrum can be realized;

[0103] The time-resolved ARPES device can use one light source to switch between two energy analyzers to achieve multifunctional time-resolved angle-resolved photoelectron energy spectrum measurement, and can measure the dynamic process of the electronic energy level structure of quantum materials, especially superconductors, topological insulators, wave density materials, etc., to provide experimental basis for revealing physical mechanisms such as superconductivity. The present invention combines the advantages of two energy analyzer ARPES, uses the same high-order harmonic light source, and can arbitrarily switch to two energy analyzer ARPES through a switching device to collect photoelectron signals, is suitable for more samples, and has important application value for the characterization and preparation of new quantum materials and condensed matter materials.

[0104] The invention discloses a time-resolved ARPES device, which is divided into two paths according to the laser propagation direction. One path is used as a detection optical path, which is sequentially provided with a high-power femtosecond laser, a high-order harmonic generation vacuum cavity, a high-order harmonic switching vacuum cavity, a monochromator vacuum cavity, a slit vacuum cavity, a high-order harmonic focusing and switching vacuum cavity, a hemispherical analyzer ARPES, and a TOF analyzer ARPES; the other path is used as a pump optical path, which is sequentially provided with a time-delay vacuum cavity, a 45-degree reflection vacuum cavity, a high-order harmonic focusing and switching vacuum cavity, a hemispherical analyzer ARPES, and a TOF analyzer ARPES; the high-power femtosecond laser is used as a detection optical path, which is sequentially provided with a high-power femtosecond laser, a high-order harmonic generation vacuum cavity, a high-order harmonic switching vacuum cavity, a hemispherical analyzer ARPES, and a TOF analyzer ARPES; Light is used to generate femtosecond laser, and the generated femtosecond laser is divided into two paths by a femtosecond beam splitter, one path is driven to generate high-order harmonics, and the other path is combined with high-order harmonics through delay to focus on the sample to generate photoelectrons, and collected by a hemispherical analyzer ARPES or a TOF ARPES, and the delay between the two paths is changed to achieve time-resolved angle-resolved photoelectron energy spectrum measurement; the time-resolved ARPES device, in the optical path, uses an electric switching system to respectively introduce the high-order harmonic beam into the hemispherical analyzer ARPES and the TOF ARPES, thereby realizing a multifunctional time-resolved ARPES device. The present invention is not only suitable for testing a variety of materials, but also can meet the needs of different users, and has universal applicability.

[0105] Compared with the prior art, the angle-resolved photoelectron spectroscopy device and the measurement method thereof of the present invention may have but are not limited to the following beneficial effects:

[0106] 1. The present invention uses high-power femtosecond laser and inert gas to interact to generate high-order harmonics in the extreme ultraviolet band as probe light, and near-infrared band femtosecond laser as pump light, which are respectively injected into the hemispherical analyzer ARPES and TOF ARPES through optical path switching to realize a multifunctional time-resolved ARPES device. The device combines the advantages of hemispherical analyzer ARPES and TOF ARPES, greatly expands the angle-resolved photoelectron energy spectrum measurement function, and is suitable for more sample testing.

[0107] 2. The present invention is based on a high-order harmonic light source in the extreme ultraviolet band. Through pump-probe technology and optical path switching, it is combined with a hemispherical analyzer ARPES and a TOF type ARPES to realize multifunctional time-resolved and angle-resolved photoelectron energy spectrum measurement functions, and realizes a time resolution of less than 200fs and an energy resolution of less than 50meV. It is used for the study of non-equilibrium phase transitions and dynamic evolution processes in condensed matter quantum materials such as high-temperature superconducting systems, exciton insulator topological materials, and charge density wave materials. The present invention can combine high harmonics with hemispherical analyzer ARPES and TOF type ARPES to realize time-resolved ARPES measurement through optical path switching. The present invention combines the advantages of hemispherical analyzer ARPES and TOF type ARPES. The high-order harmonics in the extreme ultraviolet band have the advantage of high photon energy, which will cover the non-Brillouin zone of most materials and realize the test of a higher dynamic range of electronic structure. It has important application value in the study of condensed matter and quantum materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein:

[0109] Figure 1 The schematic diagram of the structure of the angle-resolved photoelectron spectroscopy device of the present invention is shown.

[0110] Figure 2 The figure shows a perspective structural diagram of the angle-resolved photoelectron spectroscopy device of the present invention.

[0111] Figure 3 shows a schematic diagram of high-order harmonic focusing and optical path switching; wherein, Figure 3 A shows the first focusing tire mirror cuts into the high-order harmonic light path and focuses into the hemispherical analyzer ARPES; Figure 3 B shows the second focusing mirror cutting into the high-harmonic light path, focusing into the TOF analyzer ARPES.

[0112] Description of reference numerals:

[0113] 1. Laser module; 2. High-order harmonic generation vacuum cavity; 3. High-order harmonic switching vacuum cavity; 4. Monochromator vacuum cavity; 5. Slit; 6. High-order harmonic spot and energy measurement vacuum cavity; 7. High-order harmonic focusing and optical path switching module; 8. Hemispherical analyzer ARPES system module; 9. High-order harmonic introduction vacuum cavity; 10. TOF analyzer ARPES system module; 11. Pump light delay adjustment vacuum cavity; 12. Pump light guide cavity; 13. Spectrometer; 14. Gas target; 1 5. High-order harmonic generation cavity reflector; 16. Concave reflector; 17. Metal filter; 18. Extreme ultraviolet band reflector; 19. First monochromator tire mirror; 20. Grating; 21. Second monochromator tire mirror; 22. First focusing tire mirror; 23. First focusing perforated mirror; 24. Second focusing perforated mirror; 25-26, 28. Focusing reflector; 27. Focusing beam splitter; 29. ​​Second focusing tire mirror; 30. Switching perforated mirror; 31. Femtosecond beam splitter; 32. Pump reflector. DETAILED DESCRIPTION

[0114] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings. However, it should be understood that these embodiments are only used for more detailed and specific description and should not be understood as limiting the present invention in any form.

[0115] This section generally describes the materials and test methods used in the experiments of the present invention. Although many materials and operating methods used to achieve the purpose of the present invention are well known in the art, the present invention is still described as detailed as possible. It is clear to those skilled in the art that in the context, if not specifically stated, the materials and operating methods used in the present invention are well known in the art.

[0116] Example 1

[0117] This embodiment is an exemplary description of the angle-resolved photoelectron spectroscopy device and the measurement method thereof of the present invention.

[0118] like Figure 1 As shown, the angle-resolved photoelectron spectroscopy device of the present invention comprises:

[0119] A laser module for generating femtosecond laser light;

[0120] A high-order harmonics module for generating and extracting single-order high-order harmonics;

[0121] Pump light module for generating high-order harmonics;

[0122] A high-order harmonic focusing and optical path switching module for focusing the high-order harmonics onto the sample to be tested and realizing the switching of the high-order harmonics on the optical path; and

[0123] Analyzer ARPES system module used to collect the photoelectric signal emitted by the sample to be tested.

[0124] Laser module 1 is used to output femtosecond pulse laser in the 1 μm band, with an output average power of 280 W, a pulse width of 70 fs, a repetition frequency of 1 MHz, and a central wavelength of 1030 nm. It includes a femtosecond laser and a femtosecond beam splitter. The femtosecond laser emits a femtosecond laser, which is divided into two laser paths by the femtosecond beam splitter.

[0125] The high-order harmonic module includes: a high-order harmonic generating vacuum chamber 2, a high-order harmonic switching vacuum chamber 3, a monochromator vacuum chamber 4, a slit 5, and a high-order harmonic light spot and energy measurement vacuum chamber 6, which are arranged in sequence according to the laser propagation direction; the laser module 1, the high-order harmonic generating vacuum chamber 2, the high-order harmonic switching vacuum chamber 3, the monochromator vacuum chamber 4, the slit 5, the high-order harmonic light spot and energy measurement vacuum chamber 6 are arranged on the same horizontal axis.

[0126] In the high-order harmonic generation vacuum chamber 2, the incident high-power femtosecond laser is focused into the gas target by a concave reflector after mode matching, and interacts with the inert gas target to generate high-order harmonics in the extreme ultraviolet band. Specifically:

[0127] The femtosecond laser generated by the laser module is focused onto the gas target 14 by the concave reflector 16 after mode matching. The gas target sprays inert gas and interacts with the femtosecond laser to generate high-order harmonics in the extreme ultraviolet band, which enter the high-order harmonic switching vacuum cavity after passing through the high-order harmonic generating cavity reflector. The extreme ultraviolet band is preferably 16 to 60 eV, and the band selected in this embodiment is 22.8 eV.

[0128] The high-order harmonic switching vacuum chamber 3, the generated high-order harmonic beam line is coaxially transmitted with the femtosecond laser, and then the femtosecond laser is filtered out by a metal filter to extract the high-order harmonics. An ultraviolet band reflector is installed on the ultraviolet band electric translation stage. The ultraviolet band reflector is inserted into the optical path, and the high-order harmonic beam line can be introduced into the spectrometer 13 for spectral distribution measurement. The spectrometer used in this embodiment is an XUV spectrometer, specifically:

[0129] The high-order harmonic switching vacuum chamber comprises a switching perforated mirror 30, a metal filter 17, an extreme ultraviolet band reflector 18, a spectrometer 13, a mirror frame and a switching vacuum chamber electric translation stage; the extreme ultraviolet band reflector and the mirror frame are arranged together on the switching vacuum chamber electric translation stage. The high-order harmonics are coaxially transmitted with the femtosecond laser, and the femtosecond laser is guided out of the high-order harmonic switching vacuum chamber through the switching perforated mirror. The high-order harmonics pass through the small hole of the switching perforated mirror and the femtosecond laser is filtered out by the metal filter, and then are introduced into the spectrometer 13 through the extreme ultraviolet band reflector and / or propagate linearly into the monochromator vacuum chamber.

[0130] The monochromator vacuum cavity 4 collimates the generated high-order harmonics by the first monochromator tire mirror 19 and incidents on the grating for dispersion. The dispersion spot is spatially distributed according to the spectrum and then collimated by the second monochromator tire mirror 21 and output. Specifically:

[0131] The monochromator vacuum chamber includes: a first monochromator tire mirror 19, a grating 20, a second monochromator tire mirror 21, a slit 5, a slit electric translation stage, a monochromator vacuum electric translation stage and a monochromator vacuum rotating stage. The slit 5 is located on the slit electric translation stage, and the grating is located on the monochromator vacuum electric translation stage and the monochromator vacuum rotating stage. The high-order harmonics entering the monochromator vacuum chamber are collimated by the first monochromator tire mirror 19 and then enter the grating for dispersion. The dispersed light spots are spatially separated according to the wavelength. After being collimated by the second monochromator tire mirror 21, a single-order narrow-band spectrum is extracted by the slit and enters the high-order harmonic light spot and the energy measurement vacuum chamber. The slit 5 is used to extract a narrow-band spectrum from the light dispersed by the monochromator.

[0132] The high-order harmonic light spot and energy measurement vacuum chamber 6 is used to measure the brightness of the high-order harmonic light source, and includes a photodiode and a photodiode electric translation stage. The photodiode is located on the photodiode electric translation stage to measure the power of the high-order harmonics of the single-order narrow-band spectrum.

[0133] The high-order harmonic focusing and optical path switching module 7 focuses the selected narrow-band spectrum by the focusing tire mirror and combines it with the pump light to be incident on the ARPES sample. There is a focusing electric translation stage on the optical path to switch the optical path. Figure 3As shown; the high-order harmonic focusing and optical path switching module includes: a focusing electric translation stage, two focusing tire mirrors 22, 29; wherein the high-order harmonics of the single-order narrow-band spectrum are focused by the focusing tire mirror onto the sample to be tested of the hemispherical analyzer ARPES system module and / or the TOF analyzer ARPES system module and / or overlap with the pump light in space, and are jointly focused onto the sample to be tested of the hemispherical analyzer ARPES system module and / or the TOF analyzer ARPES system module;

[0134] The focusing tire mirror is mounted on the focusing electric translation stage, and the switching of high-order harmonics on the optical path is achieved by moving the focusing electric translation stage.

[0135] The analyzer ARPES system module includes: a hemispherical analyzer ARPES system module 8 and a TOF analyzer ARPES system module 9 .

[0136] Hemispherical analyzer ARPES system module 8 detects the photoelectrons generated by the interaction of high-order harmonics with the sample to obtain an angle-resolved photoelectron energy spectrum;

[0137] The high-order harmonics are introduced into the vacuum chamber 9, and an XUV reflector is installed to introduce the high-order harmonic light source and the pump light into the TOF analyzer ARPES system module 10;

[0138] The TOF analyzer ARPES system module 10 detects the photoelectrons generated by the interaction of high-order harmonics with the sample, and obtains the angle-resolved photoelectron energy spectrum through the electron flight time and angle;

[0139] The pump light module includes: a pump reflector, a pump light delay adjustment vacuum cavity for adjusting the delay between the pump light and the high-order harmonics, and a pump light guide cavity for guiding the pump light into the high-order harmonic focusing and optical path switching module, which are arranged in sequence according to the laser propagation direction;

[0140] The pump light delay adjustment vacuum chamber 11 is equipped with a delay adjustment electric translation stage for accurately changing the delay between the pump light and the high-order harmonics to achieve time-resolved measurement. The pump light delay adjustment vacuum chamber includes: 4 45-degree delay adjustment mirrors and a delay adjustment mirror frame, of which 2 delay adjustment mirrors are installed on the delay adjustment electric translation stage;

[0141] The pump light guiding cavity 12 is used to guide the pump light into the high-order harmonic focusing and optical path switching module 7 .

[0142] like Figure 1In this embodiment, the time-resolved ARPES measurement of two different functions is realized by switching the light source. Compared with the traditional single ARPES measurement scheme, it can conveniently realize the two measurement functions of TOF and hemispherical ARPES, which is more compatible and applicable.

[0143] exist Figure 1 In the method, a high-power femtosecond pulse laser 1 outputs a femtosecond laser, which is incident on a high-order harmonic generation vacuum chamber 2 after mode matching, and is focused by a concave reflector into an inert gas target to generate high-order harmonics, which are then injected into a monochromator vacuum chamber 4 to extract a single-order harmonic light source, which is incident on a high-order harmonic focusing and optical path switching module 7, and is focused by a focusing tire mirror into a hemispherical analyzer ARPES system module 8 or a TOF analyzer ARPES system module 10 to obtain an angle-resolved photoelectron energy spectrum; a small portion of the main laser is separated as pump light and injected into a pump light delay adjustment vacuum chamber 11, a pump light guide cavity 12, and then into a high-order harmonic focusing and optical path switching module 7, and is focused on an ARPES sample together with a high-order harmonic light source group, and a time-resolved ARPES measurement function is realized by changing the delay between the pump and the high-order harmonics. Specifically, the femtosecond laser emits a femtosecond laser, which is divided into two laser paths through the femtosecond beam splitter. One laser path sequentially enters a high-order harmonic generation vacuum cavity, a high-order harmonic switching vacuum cavity, a monochromator vacuum cavity, and a high-order harmonic light spot and energy measurement vacuum cavity to obtain the high-order harmonics of the single-order narrow-band spectrum, enters the high-order harmonic focusing and optical path switching module, and is focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; the other laser path sequentially enters a pump reflector, a pump light delay adjustment vacuum cavity, and a pump light guide cavity, enters the high-order harmonic focusing and optical path switching module, overlaps with the high-order harmonics of the single-order narrow-band spectrum in space, and is jointly focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

[0144] The present invention adopts high-order harmonics in the extreme ultraviolet band as a light source, and combines a hemispherical analyzer ARPES system module ARPES and a TOF analyzer ARPES system module, and realizes a time-resolved ARPES device based on an extreme ultraviolet light source through an automatic optical path switching function. It not only combines the advantages of the two analyzer ARPES, but also can better meet the needs of different samples and users, and has important significance for the detection of dynamic processes of electronic energy band structures of quantum materials, especially superconducting materials, topological insulators, density wave materials, etc.

[0145] It is universal;

[0146] The above is a detailed introduction to a time-resolved ARPES device and method provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

[0147] Although the effects of some embodiments are shown above, those skilled in the art should understand that according to the concept of the present invention, the aforementioned other embodiments without specific effects or other technical solutions of the present invention not shown in the embodiments can also achieve the following technical effects stated in the invention content section that are equivalent to the embodiments:

[0148] 1. The present invention uses high-power femtosecond laser and inert gas to interact to generate high-order harmonics in the extreme ultraviolet band as probe light, and near-infrared band femtosecond laser as pump light, which are respectively injected into the hemispherical analyzer ARPES and TOF ARPES through optical path switching to realize a multifunctional time-resolved ARPES device. The device combines the advantages of hemispherical analyzer ARPES and TOF ARPES, greatly expands the angle-resolved photoelectron energy spectrum measurement function, and is suitable for more sample testing.

[0149] 2. The present invention is based on a high-order harmonic light source in the extreme ultraviolet band. Through pump-probe technology and optical path switching, it is combined with a hemispherical analyzer ARPES and a TOF type ARPES to realize multifunctional time-resolved and angle-resolved photoelectron energy spectrum measurement functions, and realizes a time resolution of less than 200fs and an energy resolution of less than 50meV. It is used for the study of non-equilibrium phase transitions and dynamic evolution processes in condensed matter quantum materials such as high-temperature superconducting systems, exciton insulator topological materials, and charge density wave materials. The present invention can combine high harmonics with hemispherical analyzer ARPES and TOF type ARPES to realize time-resolved ARPES measurement through optical path switching. The present invention combines the advantages of hemispherical analyzer ARPES and TOF type ARPES. The high-order harmonics in the extreme ultraviolet band have the advantage of high photon energy, which will cover the non-Brillouin zone of most materials and realize the test of a higher dynamic range of electronic structure. It has important application value in the study of condensed matter and quantum materials.

[0150] Although the present invention has been described to a certain extent, it is obvious that appropriate changes in various conditions can be made without departing from the spirit and scope of the present invention. It is understood that the present invention is not limited to the embodiments described, but belongs to the scope of the claims, which includes equivalent replacements of each factor described.

Claims

1. An angle-resolved photoelectron spectroscopy device, characterized in that: The angle-resolved photoelectron spectroscopy device comprises: a laser module for generating femtosecond laser light; A high-order harmonics module for generating and extracting single-order high-order harmonics; Pump light module for generating high-order harmonics; A high-order harmonic focusing and optical path switching module for focusing the high-order harmonics onto the sample to be tested and realizing the switching of the high-order harmonics on the optical path; and An analyzer angle-resolved photoelectron spectroscopy system module for collecting photoelectric signals emitted by the sample to be tested; in: The analyzer angle-resolved photoelectron energy spectrum system module comprises: a hemispherical analyzer angle-resolved photoelectron energy spectrum system module and a time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

2. The angle-resolved photoelectron spectroscopy device according to claim 1, characterized in that: The laser module comprises a femtosecond laser and a femtosecond beam splitter, wherein the femtosecond laser emits a femtosecond laser which is split into two laser paths by the femtosecond beam splitter; The average power of the femtosecond laser is greater than 100 W, preferably greater than 150 W, more preferably greater than 200 W; and / or The pulse width of the femtosecond laser is 30 to 200 fs, preferably 30 to 150 fs, and more preferably 30 to 70 fs.

3. The angle-resolved photoelectron spectroscopy device according to claim 1 or 2, characterized in that: The high-order harmonic module includes: High harmonic generation vacuum chamber; High-order harmonic switching vacuum cavity; a monochromator vacuum chamber; and High-order harmonic light spot and energy measurement vacuum cavity; Preferably, the laser module, the high-order harmonic generation vacuum cavity, the high-order harmonic switching vacuum cavity, the monochromator vacuum cavity, the high-order harmonic light spot and the energy measurement vacuum cavity are arranged on the same horizontal axis; wherein, The high-order harmonic generation vacuum chamber comprises: a gas target, a high-order harmonic generation cavity reflector and a concave reflector; The high-order harmonic switching vacuum chamber comprises a switching perforated mirror, a metal filter, an extreme ultraviolet band reflector and a spectrometer, and the spectrometer is preferably an XUV spectrometer; The monochromator vacuum chamber comprises: a monochromator tire mirror, a grating and a slit; and / or The high-order harmonic light spot and energy measurement vacuum chamber comprises a photodiode and a photodiode electric translation stage.

4. The angle-resolved photoelectron spectroscopy device according to claim 3, characterized in that: In the high-order harmonic generation vacuum cavity: the femtosecond laser generated by the laser module is focused onto the gas target by the concave reflector after mode matching, and the gas target sprays an inert gas to interact with the femtosecond laser to generate high-order harmonics in the extreme ultraviolet band, which enter the high-order harmonic switching vacuum cavity after passing through the high-order harmonic generation cavity reflector; the extreme ultraviolet band is preferably 16 to 60 eV, more preferably 16 to 55 eV, and further preferably 16 to 50 eV; In the high-order harmonic switching vacuum cavity: the high-order harmonic is coaxially transmitted with the femtosecond laser, and is guided out of the high-order harmonic switching vacuum cavity through the switching mirror with holes and the metal filter in sequence; the high-order harmonic passes through the small hole of the switching mirror with holes and is filtered out of the femtosecond laser by the metal filter, and is guided into the spectrometer through the extreme ultraviolet band reflector and / or is linearly propagated into the monochromator vacuum cavity; In the monochromator vacuum cavity: the high-order harmonics entering the monochromator vacuum cavity are collimated by the one monochromator tire mirror and then enter the grating for dispersion, the dispersed light spots are spatially separated according to the wavelength, and after being collimated by another monochromator tire mirror, a single-order narrow-band spectrum is extracted by the slit and enters the high-order harmonic light spot and energy measurement vacuum cavity; and / or In the high-order harmonic light spot and energy measurement vacuum chamber: the photodiode is located on the photodiode electric translation stage to measure the power of the high-order harmonics of the single-order narrow-band spectrum; Preferably, the high-order harmonic switching vacuum chamber further comprises: a switching mirror frame and a switching vacuum chamber electric translation stage, the extreme ultraviolet band reflector and the switching mirror frame are jointly arranged on the switching vacuum chamber electric translation stage; and / or Preferably, the monochromator vacuum chamber further comprises: a slit electric translation stage, a monochromator vacuum electric translation stage and a monochromator vacuum rotating stage, the slit is located on the slit electric translation stage, and the grating is located on the monochromator vacuum electric translation stage and the monochromator vacuum rotating stage.

5. The angle-resolved photoelectron spectroscopy device according to any one of claims 1 to 4, characterized in that: The pump light module includes: Pump reflector; A pump light delay adjustment vacuum cavity for adjusting the delay between the pump light and the high-order harmonics; and A pump light guiding cavity for guiding the pump light into the high-order harmonic focusing and optical path switching module; Preferably, the pump light delay adjustment vacuum chamber comprises: a delay adjustment reflector, a delay adjustment mirror frame and a delay adjustment electric translation stage.

6. The angle-resolved photoelectron spectroscopy device according to claim 4 or 5, characterized in that: The high-order harmonic focusing and optical path switching module includes: a focusing tire mirror and a focusing electric translation stage; wherein, The single-order narrow-band spectrum high harmonics selected by the monochromator in the monochromator vacuum chamber are focused by the focusing tire mirror onto the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module to obtain an angle-resolved photoelectron energy spectrum; and / or The single-order narrow-band spectrum high harmonics selected by the monochromator in the monochromator vacuum cavity are focused by the focusing tire mirror, overlapped with the pump light in space, and focused together on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; Preferably, the focusing tire mirror is mounted on the focusing electric translation stage, and the switching of high-order harmonics on the optical path is achieved by moving the focusing electric translation stage; and / or Preferably, the high-order harmonic focusing and optical path switching module further comprises: a focusing perforated mirror, a focusing reflector and a focusing beam splitter.

7. The angle-resolved photoelectron spectroscopy device according to any one of claims 1 to 6, characterized in that: The angle-resolved photoelectron spectroscopy device comprises: a high-order harmonic introduction vacuum cavity; wherein, The high-order harmonic introduction vacuum chamber is equipped with an introduction reflector of an electric mirror holder; and / or The high-order harmonic introduction vacuum chamber introduces the high-order harmonics output by the high-order harmonic focusing and optical path switching module into the hemispherical analyzer angle-resolved photoelectron spectroscopy system module and / or the time-of-flight analyzer angle-resolved photoelectron spectroscopy system module.

8. The angle-resolved photoelectron spectroscopy device according to any one of claims 1 to 7, characterized in that: The hemispherical analyzer angle-resolved photoelectron energy spectrum system module collects the photoelectron signal emitted by the sample to be tested to obtain an angle-resolved photoelectron energy spectrum, and obtains a time-resolved angle-resolved photoelectron energy spectrum by changing the time delay between the pump light and the high-order harmonics; and / or The time-of-flight analyzer angle-resolved photoelectron energy spectrum system module collects photoelectron signals emitted by the sample to be tested, measures the flight time and the emission angle to obtain the angle-resolved photoelectron energy spectrum, and obtains the time-resolved angle-resolved photoelectron energy spectrum by changing the time delay between the pump light and the higher harmonics.

9. A method for measuring angle-resolved photoelectron spectroscopy, characterized in that: The measurement method uses the device described in any one of claims 1 to 8 to measure the angle-resolved photoelectron energy spectrum; Preferably, the measuring method comprises the steps of: The laser module generates femtosecond laser and divides it into two paths. One path of laser light enters the high-order harmonic module and the high-order harmonic focusing and optical path switching module in sequence, and is respectively focused on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; the other path of laser light enters the pump light delay adjustment vacuum cavity, the pump light guide cavity and the high-order harmonic focusing and optical path switching module in sequence, overlaps with the high-order harmonic beam line in space, and is jointly focused on the sample to be tested of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

10. A method for measuring angle-resolved photoelectron spectroscopy, characterized in that: The measurement method uses the device described in any one of claims 4 to 8 to measure the angle-resolved photoelectron energy spectrum; Preferably, the measuring method comprises the steps of: The femtosecond laser emits a femtosecond laser, which is divided into two laser paths through the femtosecond beam splitter. One laser path enters the high-order harmonic generation vacuum cavity, the high-order harmonic switching vacuum cavity, the monochromator vacuum cavity, and the high-order harmonic light spot and energy measurement vacuum cavity in sequence to obtain the high-order harmonics of the single-order narrow-band spectrum, enters the high-order harmonic focusing and optical path switching module, and is focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module; the other laser path enters the pump reflector, the pump light delay adjustment vacuum cavity, and the pump light guide cavity in sequence, enters the high-order harmonic focusing and optical path switching module, overlaps with the high-order harmonics of the single-order narrow-band spectrum in space, and is jointly focused on the sample to be measured of the hemispherical analyzer angle-resolved photoelectron energy spectrum system module and / or the time-of-flight analyzer angle-resolved photoelectron energy spectrum system module.

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