Self-Powered FTO/CdSe/Bi2Se3 Photodetector with Bipolar Photoresponse Characteristics

absorber, combined with the photogenerated carriers separated by asymmetric back-to-back diode, a wavelength-dependent bipolar response is realized. In this work, by employing this structure, the responsivities of -33.3 and 0.3 mA/W were achieved under the illumination of 405 and 830 nm, respectively. This work provides important indications in the preparation and performance optimization for wavelength-dependent bipolar photodetectors.