High-efficiency quantum rectenna for millimeter wave and terahertz technologies*

We propose a new concept for rectenna that utilizes the nonlinear transverse current-voltage characteristic of junction-free quantum materials to rectify millimeter and terahertz waves into DC electricity. We analyze the rectification efficiency defined by the ratio of the DC output power to the AC input power. We show that the efficiency can be determined from the measurement of the DC transverse voltage as a function of the AC input current. High efficiency on the order of unity can be achieved when the photoconductivity is small, as we calculate explicitly for time-reversal-breaking semiconductors with non-parabolic bands and Rashba systems. Our proposed rectenna also has an advantage in impedance matching between the rectifier and the antenna, and the rectifier and the external load.