Notable peak voltage and sensitivity as well as optical-communication of the inclined Bi2Sr2CuOy thin film with different wavelength lasers

Abstract

In this work, the laser-induced thermoelectric voltage (LITV) of the solution-deposited inclined Bi₂Sr₂CuO_y (BSCO) thin films with different wavelength semiconductor lasers was investigated. Microstructure results indicate the BSCO thin film inclined growth along the substrate with the same angle. Obvious LITV keeps a linear increase with the increased power density for each wavelength laser. The peak voltage is over 40 mV at the power density of 40 mW/cm². It is slightly different with the laser wavelength, caused by the difference in optical absorption and light penetration depth. The sensitivity is higher than 0.8 and increases to 1.15 V·cm²/W with the laser changes from green to ultraviolet. Furthermore, based on the LITV effect of the BSCO thin film, the carry information can be transmitted and decoded correctly via the optical communications system composed of the light diode laser. All these results demonstrate the potential application and favorable properties of the inclined BSCO thin films in broad-spectrum response of photodetection.