Electrically tunable charge and spin transitions in Landau levels of interacting Dirac fermions in trilayer graphene

TL;DR

This paper investigates how bias voltage can electrically control charge and spin transitions in Landau levels of interacting Dirac fermions in trilayer graphene, revealing tunable quantum Hall effects and spin polarization changes.

Contribution

It demonstrates that bias voltage can tune interaction-induced charge and spin transitions in Landau levels of trilayer graphene, especially near anti-crossing points, enabling control over spin polarization.

Findings

Bias voltage controls Landau level transitions in trilayer graphene.

Transitions involve changes in charge and spin polarization.

Unusual transitions occur at anti-crossing points under high magnetic fields.

Abstract

Trilayer graphene in the fractional Quantum Hall Effect regime displays a set of unique interaction-induced transitions that can be tuned entirely by the applied bias voltage. These transitions occur near the anti-crossing points of two Landau levels. In a large magnetic field ($> 8$ T) the electron-electron interactions close the anti-crossing gap, resulting in some unusual transitions between different Landau levels. For the filling factor $\nu=\frac23$, these transitions are accompanied by a change of spin polarization of the ground state. For a small Zeeman energy, this provides an unique opportunity to control the spin polarization of the ground state by fine tuning the bias voltage.