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

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.