Materials that rectify light into the current in their bulk are preferred for optoelectronic applications. Bulk photocurrents may develop in Weyl semimetals with broken inversion symmetry due to intensified nonlinear optical processes close to the Weyl nodes. Nevertheless, scanning photocurrent microscopy, which muddles the effects of photocurrent generation and collecting, is frequently used to study the photoresponse of these materials.
Scientists from Boston College have revealed a surprising new mechanism for converting light into electricity in Weyl semimetals using quantum sensors. They have shown that the spatial asymmetry within a single material can generate spontaneous photocurrents.
Scientists examined two materials: tungsten ditelluride and tantalum iridium tetratelluride. Both materials belong to the class of Weyl semimetals.
According to scientists, these materials would be a great choice for generating photocurrent because their crystal structure is inherently inversion asymmetric. It means their crystal does not map onto itself by reversing directions about a point.