Room-temperature valley transistors for low-power neuromorphic computing

Valley pseudospin is an electronic degree of freedom that promises highly efficient information processing applications. However, valley-polarized excitons usually have short pico-second lifetimes, which limits the room-temperature applicability of valleytronic devices. Here, we demonstrate room-temperature valley transistors that operate by generating free carrier valley polarization with a long lifetime. This is achieved by electrostatic manipulation of the non-trivial band topology of the Weyl semiconductor tellurium (Te). We observe valley-polarized diffusion lengths of more than 7 mu m and fabricate valley transistors with an ON/OFF ratio of 10(5) at room temperature. Moreover, we demonstrate an ion insertion/extraction device structure that enables 32 non-volatile memory states with high linearity and symmetry in the Te valley transistor. With ultralow power consumption (similar to fW valley contribution), we enable the inferring process of artificial neural networks, exhibiting potential for applications in low-power neuromorphic computing.

Automated summary

This study demonstrates room-temperature valley transistors with long-lived free carrier valley polarization, achieved by electrostatic manipulation of the non-trivial band topology of the Weyl semiconductor. The researchers observed valley-polarized diffusion lengths of over 7 μm and fabricated valley transistors with a high ON/OFF ratio. Additionally, they established an ion insertion/extraction device structure that enables high linearity and symmetry in the non-volatile memory states of the valley transistor.