Asymmetric Dual Grating Gate Graphene-based THz detectors

We report on detection of terahertz radiation by using asymmetric dual-grating gates graphene-based FET. The graphene sheet was sandwiched between two layers of hexagonal Boron Nitride (h-BN) to avoid interaction with the substrate and enhance carrier mobility. Asymmetric dual metal gates were processed on the top of the upper h-BN layer. The devices were excited with terahertz radiation at frequencies of 0.15 and 0.3 THz and a clear photocurrent was observed from 4K up to room temperature.