Effect of current-induced electron heating on irradiated magnetoresistance in high-mobility 2D electron systems

Escuela Politecnica Superior, Universidad Carlos III de Madrid - Madrid, 28911, Spain and Unidad Asociada al Instituto de Ciencia de Materiales, CSIC - Cantoblanco, Madrid, 28049, Spain

Received: 14 June 2019
Accepted: 25 August 2019

Abstract

We present a theoretical work to study the influence of an external DC-current on the irradiated magnetoresistance through a very high-mobility 2D electron system. Recent experiments report that an increasing DC-current through the system under radiation, dramatically reduces magnetoresistance, including background and irradiated contributions. On the one hand, the former ends up progressively negative (negative giant magnetoresistance) and on the other hand, the effect of radiation, i.e., the radiation-induced resistance oscillations, tends to vanish. In our theoretical model, the DC-current–induced hot electrons when scattered by charged impurities end up, to an increasing extent, between Landau levels with a very low density of states to get to. This makes the scattering process much less effective, decreasing both the magnetoresistance itself and the radiation-induced resistance oscillations. We conclude that both effects are not separable, being tightly linked by the scattering process.