Nanoscale graphene/Ge wigglers as building blocks for THz sources

Abstract

We demonstrate that wrinkled graphene on Ge with nanoscale period and amplitude holds the potential to generate cyclotron-like radiation in the THz range of the electromagnetic spectrum. We show nanoscale graphene wigglers fabricated by release and transfer of atomically thin sheets to one-dimensional Ge gratings. We present a simple time of flight and interference model to calculate the radiated frequency and output power for the fabricated devices. We establish, theoretically, that an output power of ∼ 0.1-7 mW can be obtained from graphene/Ge wigglers with period not exceeding 85 nm, and amplitude-to-period ratio in the range of 1.4 to 10.