Terahertz rectification by plasmons and hot carriers in gated 2D electron gases

Here we discuss on detection using antenna-coupled field effect transistors. We show, that gate-to-channel separation plays strong role for the dispersion of plasmons excited within the channel changing from gated 2D to ungated 2D plasmon. This change also strongly affects the impedance and the efficiency of rectification. We present experimental data which clearly indicates on with plasmonic rectification competing physical phenomenon. There are strong indications, that this additional signal originates from the inhomogeneous heating of charge carriers i.e., diffusion of “warm” electrons.