We present phenomenological analysis of the period and the phase of microwave-induced resistance oscillations (MIRO) and “zero-resistance” states (ZRS) recently observed in two-dimensonal electron systems. While MIRO are found to be well described by a “1/4-cycle shift,” we find that as MIRO evolve into ZRS with increasing magnetic field B, the phase becomes progressively smaller, decreasing roughly as 1/B.As a result, both maxima and minima in the ZRS regime form periodic in 1/B sequences, without a 1/4-cycle shift. A simple model based on oscillatory density of states is found to provide a unified description of the period/phase of MIRO/ZRS and leads to an interpretation of previously reported fine structures in terms of multiphoton processes.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Jan 22 2004|