Application of variable temperature fluorescence test system with adjustable pump intensity in quasi-2D perovskite materials

The properties of excitons have a decisive influence on the luminescence mechanism of two-dimensional perovskite materials. Measuring exciton-phonon coupling strength and exciton binding energy is a powerful method to study the characteristics of excitons in quasi-two-dimensional perovskite materials, which can be used to reveal Its internal light emission mechanism and further improvement of fluorescence quantum yield provide a key scientific basis. Combining a variable light intensity fluorescence test system and a liquid nitrogen constant temperature device, using the LABVIEW program for system control, a set of variable temperature with adjustable light intensity is built The fluorescence test system, and the quasi-two-dimensional perovskite film sample as the research object, has carried out the study of the excitons and the luminescence properties of the two-dimensional perovskite. The research results show that: with the quasi-two-dimensional perovskite materialWith the increase of the value, the exciton-longitudinal optical phonon coupling strength and exciton binding energy are gradually reduced. In addition, the test system was used to perform variable light intensity fluorescence measurements at room temperature, and the optical gain of the quasi-two-dimensional perovskite film was explored. , The amplified spontaneous emission threshold is 3.2μJ/cm2.