Synchnonization, zero-resistance states and rotating Wigner crystal

TL;DR

This paper demonstrates that external microwave fields can synchronize electron rotations in 2D systems, leading to zero-resistance states by preventing collisions, and suggests a connection to rotating Wigner crystals and planetary rings.

Contribution

It introduces a mechanism for electron synchronization via microwave fields that results in zero-resistance states and describes the formation of a rotating Wigner crystal.

Findings

Synchronization eliminates electron collisions.

Zero-resistance states are achieved in high mobility 2DEG.

Electrons form a rotating hexagonal Wigner crystal.

Abstract

We show that rotational angles of electrons moving in two dimensions (2D) in a perpendicular magnetic field can be synchronized by an external microwave field which frequency is close to the Larmor frequency. The synchronization eliminates collisions between electrons and thus creates a regime with zero diffusion corresponding to the zero-resistance states observed in experiments with high mobility 2D electron gas (2DEG). For long range Coulomb interactions electrons form a rotating hexagonal Wigner crystal. Possible relevance of this effect for planetary rings is discussed.