Electrically tunable charge and spin transitions in Landau levels of   interacting Dirac fermions in trilayer graphene
  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. 
Vadim M. Apalkov (Georgia State University), Tapash Chakraborty   (University of Manitoba)
cond-mat.str-el cond-mat.mes-hall