Investigating microwave absorption in asymmetric Si quantum wells in an external magnetic field, we discover a spin dependent component of Joule heating at spin resonance. We explain this effect in terms of Rashba spin-orbit coupling which results in a current induced spin precession and Zitterbewegung. Evidence is based on the observation of a specific dependence of the electron spin resonance line shape and its amplitude on the experimental geometry which in some range suggests a "negative" differential power absorption.
@article{arxiv.1001.3746,
title = {Spin Dependent Joule Heating due to Rashba Coupling and Zitterbewegung},
author = {Z. Wilamowski and W. Ungier and M. Havlicek and W. Jantsch},
journal= {arXiv preprint arXiv:1001.3746},
year = {2010}
}