Wide-band frequency-selective terahertz detection based on a single-layer graphene

We report on a new type of terahertz (THz) detector based on a single-layer graphene. We have observed experimentally that the graphene under a magnetic field is able to detect THz waves ranging from far-infrared to mid-infrared region. This is due to unique Landau-level formation of Dirac fermions, which is in strong contrast to electronic systems of conventional semiconductors. The present observation leads to a very wide-band frequency-selective THz detector.