Interaction-induced merging of Landau levels in an electron system of double quantum wells

TL;DR

This paper demonstrates that electron interactions cause Landau level merging in double quantum wells, leading to the disappearance of chemical potential jumps at fixed integer filling factors under magnetic fields.

Contribution

It reveals that interaction-induced level merging explains the vanishing of chemical potential jumps in double quantum wells, a novel insight into electron behavior under magnetic fields.

Findings

Level merging caused by electron interactions in double quantum wells.

Disappearance of chemical potential jumps at fixed integer filling factors.

Unique distribution function in the merging regime.

Abstract

We show that the disappearance of the chemical potential jumps over the range of perpendicular magnetic fields at fixed integer filling factor in a double quantum well with a tunnel barrier is caused by the interaction-induced level merging. The distribution function in the merging regime is special in that the probability to find an electron with energy equal to the chemical potential is different for the two merged levels.