Evolution of Shubnikov-de Haas oscillations under photoexcitation in the regime of the radiation-induced zero-resistance states

We examine the variation of the amplitude of Shubnikov-de Haas (SdH) oscillations under the influence of photoexcitation in the regime of the radiation-induced zero-resistance states in GaAs/AlGaAs devices. We find that the SdH amplitude scales linearly with the average background resistance in the vicinity of the radiation-induced resistance minima. The results show that the SdH amplitude vanishes in proportion to the background resistance at the centers of the zero-resistance states.