The nonlinear effect of transport current on the response of metals to electromagnetic radiation

Abstract

The nonlinear interaction of DC current flowing in a thin metal film with an external low-frequency AC electromagnetic field is studied theoretically. The nonlinearity is related to the influence of the magnetic field of the DC current and the magnetic field of the wave on the form of electron trajectories. This magnetodynamic mechanism of nonlinearity is the most typical for pure metals at low temperatures. We find that such interaction causes sharp kinks in the temporal dependence of the AC electric field of the wave on surface of the sample. The phenomenon of amplification of the electromagnetic signal on the metal surface is predicted. We also calculate the nonlinear surface impedance and show that it turns out to be imaginary-valued and its modulus decreases drastically with the increase of the wave amplitude.

Magnetodynamical instability in aluminum in the Rinzel–Keller model

“…The action of the magnetic field of electromagnetic wave or strong electric current causes variation in conductivity of pure metal. Several kinds of instabilities can be generated due to this magnetodynamical nonlinearity [1][2][3]. Propagation of high-frequency electromagnetic wave presents an effective method for studying pulse current instability.…”