A research team led by Prof. Wang Xianlong and Dr. Wang Pei from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has discovered a concurrent negative photoconductivity (NPC) and superconductivity in PbSe0.5 Te0.5 by pressure-induced structure transition. The study has been published in Advanced Materials.
NPC is a unique phenomenon where the conductivity of a material decreases due to the trapping of charge carriers in localized states, leading to a reduction in the number of free carriers, which is contrary to the more common behavior of positive photoconductivity (PPC).
Though NPC holds great promise in next-generation semiconductor optoelectronics and its application potential has recently reached far beyond photodetection, the phenomenon has rarely been reported. In particular, concurrent NPC and superconductivity are rarely observed at high-pressure due to the lack of in situ experimental measuring facilities.