Plasmonic and bolometric terahertz graphene sensors

We demonstrate that graphene field effect transistors can operate as both plasmonic and bolometric THz sensors depending on polarization and bias configurations. The plasmonic mechanism of detection is consistent with the overdamped plasma wave response. The bolometric regime is caused by the shift of the Dirac point with temperature and reveals the asymmetry in the electron and hole response associated with long-lived impurity centers responsible for the shift of the Dirac voltage.