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Universal Magnetic Oscillations of dc Conductivity in the Incoherent Regime of Correlated Systems
December 13, 2021 @ 11:35 - 12:00 CET
J. Vučičević,1 R. Žitko2,3
1Scientific Computing Laboratory, Center for the Study of Complex Systems, Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia
2Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
3Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, SI-1000 Ljubljana, Slovenia
Using the dynamical mean field theory we investigate the magnetic field dependence of dc conductivity in the Hubbard model on the square lattice, fully taking into account the orbital effects of the field introduced via the Peierls substitution. In addition to the conventional Shubnikov–de Haas quantum oscillations, associated with the coherent cyclotron motion of quasiparticles and the presence of a well-defined Fermi surface, we find an additional oscillatory component with a higher frequency that corresponds to the total area of the Brillouin zone. These paradigm-breaking oscillations appear at elevated temperature. This finding is in excellent qualitative agreement with the recent experiments on graphene superlattices. We elucidate the key roles of the off-diagonal elements of the current vertex and the incoherence of electronic states, and explain the trends with respect to temperature and doping.
- J. Vučičević and R. Žitko, “Universal magnetic oscillations of dc conductivity in the incoherent regime of correlated systems,” Phys. Rev. Lett. 127, 196601 (2021).
- J. Vučičević and R. Žitko, “Electrical conductivity in the Hubbard model: Orbital effects of magnetic field,” Phys. Rev. B 104, 205101 (2021).