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arXiv · 0707.2078

Quantum transport of Dirac electrons in graphene in the presence of a spatially modulated magnetic field

M. Tahir·K. Sabeeh
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Abstract

We have investigated the electrical transport properties of Dirac electrons in a monolayer graphene sheet in the presence of a perpendicular magnetic field that is modulated weakly and periodically along one direction.We find that the Landau levels broaden into bands and their width oscillates as a function of the band index and the magnetic field.We determine the $σ_{yy}$ component of the magnetoconductivity tensor for this system which is shown to exhibit Weiss oscillations.We also determine analytically the asymptotic expressions for $σ_{yy}$.We compare these results with recently obtained results for electrically modulated graphene as well as those for magnetically modulated conventional two-dimensional electron gas (2DEG) system.We find that in the magnetically modulated graphene system cosidered in this work,Weiss oscillations in $σ_{yy}$ have a reduced amplitude compared to the 2DEG but are less damped by temperature while they have a higher amplitude than in the electrically modulated graphene system. We also find that these oscillations are out of phase by $π$ with those of the electrically modulated system while they are in phase with those in the 2DEG system.

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M. Tahir, K. Sabeeh. 2008-04-11. Quantum transport of Dirac electrons in graphene in the presence of a spatially modulated magnetic field. https://doi.org/10.1103/physrevb.77.195421

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