Extremely high-performance visible light photodetector in the Sb₂SeTe₂ nanoflake

The photocurrent was performed in the Sb₂SeTe₂ topological insulator at a wavelength of 532 nm. It exhibits extremely high performance that the responsivity and the photoconductive gain reach 2293 AW^-1 and 5344 at 1 V. This high photoresponse is orders of magnitude higher than most reported values in topological insulators and two-dimensional transitional metal dichalcogenides. This finding suggests that the Sb₂SeTe₂ nanoflake has great potential for future optoelectronic device applications.