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arXiv · 1109.3348

Landau levels in deformed bilayer graphene at low magnetic fields

M. Mucha-Kruczynski·I. L. Aleiner·V. I. Fal'ko
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Abstract

We review the effect of uniaxial strain on the low-energy electronic dispersion and Landau level structure of bilayer graphene. Based on the tight-binding approach, we derive a strain-induced term in the low-energy Hamiltonian and show how strain affects the low-energy electronic band structure. Depending on the magnitude and direction of applied strain, we identify three regimes of qualitatively different electronic dispersions. We also show that in a weak magnetic field, sufficient strain results in the filling factor ff=+-4 being the most stable in the quantum Hall effect measurement, instead of ff=+-8 in unperturbed bilayer at a weak magnetic field. To mention, in one of the strain regimes, the activation gap at ff=+-4 is, down to very low fields, weakly dependent on the strength of the magnetic field.

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M. Mucha-Kruczynski, I. L. Aleiner, V. I. Fal'ko. 2011-09-15. Landau levels in deformed bilayer graphene at low magnetic fields. https://doi.org/10.1016/j.ssc.2011.05.019

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