Nanowerk March 24, 2022
An international team of researchers (Spain, USA – Columbia University, Japan, Singapore)
showed that by applying circular polarized infrared light onto the bilayer graphene device, they could selectively excite one specific valley population of electrons in the material, which generated a photovoltage perpendicular to the usual electron flow. By engineering the device and setup in such a way that current only flows with light illumination, they were able to avoid the background noise that hampers measurements and achieved a sensitivity in the detection several orders of magnitude better than any other 2D material. They could control the bending of the electrons with the out-of-plane electric field, change the bending angle of the electrons. The finding could have implications for infrared and terahertz sensing, imaging in space, and medical imaging…read more. Video TECHNICAL ARTICLEÂ
Artistic impression for the valley-selective Hall effect. Credit: ICFO/ Matteo Ceccanti