S.O. Potashin, V. Yu. Kachorovskii, M. Shur
Rensselaer Polytechnic Institute,
Keywords: terahertz technology, plasmonics, inverse Faraday effect, tunable absorber
Summary:We describe and analyze a tunable resonant absorber and modulator of electromagnetic radiation using arrays of nanospheres or nanorings in the vicinity of (or embedded into) a gated two-dimensional electron liquid (2DEL). A circularly polarized electromagnetic wave impinging on the nanospheres creates a system of rotating dipoles inducing circular plasmonic modes (twisted plasmons) in the 2DEL. Rectification of these plasmonic waves due to the 2DEL hydrodynamic nonlinearities leads to helicity-sensitive circular DC current, and consequently, to a magnetic moment. If the nanospheres form a 2D crystal the entire high-mobility 2DEL experiences a resonant circular plasmonic excitation resulting in giant rectified resonant DC current oscillating in space. Since the resonant plasma wave frequency is tunable by the gate voltage and/or by an external magnetic field such a system can be used for the optical tunable magnetization of the 2DEL systems. Our estimates show that these an external magnetic field such a system can be used for the optical tunable magnetization of the 2DEL systems. Our estimates show that these effects could be observed in Si, GaN, InGaAs, and p-diamond materials systems enabling many applications in the terahertz frequency range even at room temperature.