CN-122026208-A - Terahertz generation system based on perovskite and organic crystal

CN122026208ACN 122026208 ACN122026208 ACN 122026208ACN-122026208-A

Abstract

The invention discloses a terahertz generation system based on perovskite and organic crystals, which comprises a femtosecond laser pumping source, an optical modulation unit, a sample bearing platform, a terahertz signal detection unit and a signal processing unit, wherein the femtosecond laser pumping source is used for generating high-intensity ultrashort pulse femtosecond laser, the optical modulation unit is arranged on an optical path between the femtosecond laser pumping source and a crystal sample and used for modulating the wavelength, intensity or phase of the femtosecond laser, the sample bearing platform is used for placing a two-dimensional/zero-dimensional perovskite crystal or a modified organic crystal sample, the terahertz signal detection unit is used for collecting and detecting terahertz radiation generated from the crystal sample, and the signal processing unit is used for analyzing terahertz signals output by the detection unit. The invention discloses a terahertz generation system based on perovskite and organic crystals, which aims to overcome the defects of low conversion efficiency, limited tuning range, complex system or high cost in the existing terahertz generation technology.

Inventors

LIN KE
SONG YUNHE
ZHAO LIXIA
WANG MENG

Assignees

浙江大学绍兴研究院

Dates

Publication Date: 20260512
Application Date: 20251226

Claims (5)

1. A terahertz generation system based on perovskite and organic crystals, comprising: the femtosecond laser pumping source is used for generating high-intensity and ultrashort pulse femtosecond laser; The optical modulation unit is arranged on the optical path between the femtosecond laser pumping source and the crystal sample and is used for modulating the wavelength, the intensity or the phase of the femtosecond laser; the sample bearing platform is used for placing a two-dimensional/zero-dimensional perovskite crystal or modified organic crystal sample; A terahertz signal detection unit for collecting and detecting terahertz radiation generated from the crystal sample; the signal processing unit is used for analyzing the terahertz signal output by the detection unit; the femtosecond laser is irradiated by using a two-dimensional/zero-dimensional perovskite crystal or a modified organic crystal with nonlinear optical characteristics as a medium, and tunable terahertz radiation is generated through the nonlinear optical process of the medium.
2. The terahertz generation system based on perovskite and organic crystal according to claim 1, wherein the frequency and bandwidth of terahertz radiation are tuned by at least one of the following means: Chemical tuning, namely changing the chemical composition of perovskite crystals, including halogen element replacement, ion doping or structural modification; Structure tuning, namely adjusting the growth condition of the crystal to change the dimension, defect state, size, shape or orientation of the crystal; pump tuning, which is to adjust the wavelength, intensity or pulse characteristics of the femtosecond pump laser or modulate the pump light parameters through an electro-optic/acousto-optic modulator.
3. The terahertz generation system based on perovskite and organic crystals according to claim 1, wherein the center wavelength of the femtosecond laser pumping source is adjustable to adapt to the nonlinear optical response requirements of different crystal materials.
4. The terahertz generation system based on perovskite and organic crystal according to claim 1, wherein the perovskite crystal comprises a lead-free perovskite analog 、 And tin doped CBI, CBBI derivatives, and modified organic crystals including DAST and modified forms thereof.
5. The terahertz generation system based on perovskite and organic crystal according to claim 4, wherein the synthesis method of the medium comprises: Preparing single crystal, namely placing the precursor solution into an oil bath for heating and inducing crystallization to obtain high-quality perovskite single crystal; Preparing a two-dimensional perovskite crystal film by a solution method and a polycrystalline film deposition technology of vacuum evaporation; The performance regulation and control comprises regulating and controlling the valence state and absorption characteristic of the material by doping Sn element, and realizing the engineering design of crystal size, morphology, orientation and defects by controlling parameters of growth temperature, pressure and stoichiometric ratio.

Description

Terahertz generation system based on perovskite and organic crystal Technical Field The invention belongs to the technical field of terahertz generation, and particularly relates to a terahertz generation system based on perovskite and organic crystals. Background Terahertz (THz) radiation is located between microwaves and infrared light in the electromagnetic spectrum, and its unique spectral characteristics make it of irreplaceable application potential in the fields of imaging, spectroscopy, high-speed communication, security inspection, biomedical detection, etc. However, the industrialized popularization of terahertz technology is limited by the bottleneck of core devices, especially the lack of terahertz sources which are efficient, low-cost, tunable and compact. The existing terahertz generation technology mainly comprises schemes such as a photoconductive antenna, optical rectification and difference frequency generation, but has the obvious defects that the conversion efficiency of the photoconductive antenna is low and is limited by the response speed of materials, nonlinear crystals (such as ZnTe and GaP) which are relied on by the traditional optical rectification technology have the problems of low nonlinear coefficient and narrow tuning range, and the difference frequency generation technology needs complex pump light source configuration, so that the system is huge in volume and high in cost. Therefore, the development of novel high-performance nonlinear dielectric materials and the construction of terahertz generation technology with the advantages of high efficiency, wide tuning and low cost become a research hotspot and a key breakthrough direction in the field. Disclosure of Invention The invention mainly aims to provide a terahertz generation system based on perovskite and organic crystals, which aims to overcome the defects of low conversion efficiency, limited tuning range, complex system or high cost in the existing terahertz generation technology, and realizes a compact terahertz source which is efficient, tunable and works at room temperature through material system innovation and structural design. To achieve the above object, the present invention provides a terahertz generation system based on perovskite and organic crystal, comprising: the femtosecond laser pumping source is used for generating high-intensity and ultrashort pulse femtosecond laser; The optical modulation unit is arranged on the optical path between the femtosecond laser pumping source and the crystal sample and is used for modulating the wavelength, the intensity or the phase of the femtosecond laser; the sample bearing platform is used for placing a two-dimensional/zero-dimensional perovskite crystal or modified organic crystal sample; A terahertz signal detection unit for collecting and detecting terahertz radiation generated from the crystal sample; the signal processing unit is used for analyzing the terahertz signal output by the detection unit; the femtosecond laser is irradiated by using a two-dimensional/zero-dimensional perovskite crystal or a modified organic crystal with nonlinear optical characteristics as a medium, and tunable terahertz radiation is generated through the nonlinear optical process of the medium. As a further preferable technical solution of the above technical solution, the frequency and bandwidth of the terahertz radiation are tuned by at least one of the following means: Chemical tuning, namely changing the chemical composition of perovskite crystals, including halogen element replacement, ion doping or structural modification; Structure tuning, namely adjusting the growth condition of the crystal to change the dimension, defect state, size, shape or orientation of the crystal; pump tuning, which is to adjust the wavelength, intensity or pulse characteristics of the femtosecond pump laser or modulate the pump light parameters through an electro-optic/acousto-optic modulator. As a further preferable technical scheme of the technical scheme, the center wavelength of the femtosecond laser pumping source is adjustable, and the nonlinear optical response requirements of different crystal materials are adapted. As a further preferable embodiment of the above technical scheme, the perovskite crystal includes a lead-free perovskite analogue、And tin doped CBI, CBBI derivatives, and modified organic crystals including DAST and modified forms thereof. As a further preferable technical scheme of the technical scheme, the method for synthesizing the medium comprises the following steps: Preparing single crystal, namely placing the precursor solution into an oil bath for heating and inducing crystallization to obtain high-quality perovskite single crystal; Preparing a two-dimensional perovskite crystal film by a solution method and a polycrystalline film deposition technology of vacuum evaporation; The performance regulation and control comprises regulating and controlling the valence state and