Nonreciprocal Waves in Two-Dimensional Electron Systems with Temperature Gradient

We demonstrate that the interaction of dc temperature gradient with ac magnetic field in temperature-biased two-dimensional electron systems leads to formation of a new electromagnetic mode, a two-dimensional thermomagnetic wave (2D TMW). This wave is transverse electric and nonreciprocal, and its damping rate can be lower than that of conventional 2D plasma waves. The $$Q$$ -factor of 2D TMW is independent of the wave vector. Numerical estimates show that in state-of-the-art two-dimensional electrons systems the 2D TMW $$Q$$ -factor is the order of 10 –3 . We discuss possible ways to overcome this issue.