Proposal for an electrically controlled terahertz micro-oscillator

A source that generates sustained terahertz electromagnetic radiation (oscillator) controllable by an applied voltage is proposed. The structure consists of a nanocomposite slab containing metal nanorods enclosed between two graphene sheets, which are electrostatically gated. The principle of its operation is based on a positive feedback that the nanorod polarization experiences from the radiation reflected using the graphene mirrors. The self-excitation process developed in this structure can be powered by a weak broadband source of terahertz radiation, in particular, by a heated wire that emits black-body radiation. The proposed approach can provide a microscopic source of monochromatic polarized terahertz radiation of power sufficient for biomedical and security applications, which is compatible with the lab-on-a-chip technology.