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arXiv · 0707.3543

Quantisation of Hopping Magnetoresistance Prefactor in Strongly Correlated Two-Dimensional Electron Systems

Matthias Baenninger·Arindam Ghosh·Michael Pepper·Harvey E. Beere·Ian Farrer·Paula Atkinson·Dave A. Ritchie
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Abstract

We report an universal behaviour of hopping transport in strongly interacting mesoscopic two-dimensional electron systems (2DES). In a certain window of background disorder, the resistivity at low perpendicular magnetic fields follows the expected relation $ρ(B_\perp) = ρ_{\rm{B}}\exp(αB_\perp^2)$. The prefactor $ρ_{\rm{B}}$ decreases exponentially with increasing electron density but saturates to a finite value at higher densities. Strikingly, this value is found to be universal when expressed in terms of absolute resistance and and shows quantisation at $R_{\rm{B}}\approx h/e^2$ and $R_{\rm{B}}\approx 1/2$ $ h/e^2$. We suggest a strongly correlated electronic phase as a possible explanation.

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Matthias Baenninger, Arindam Ghosh, Michael Pepper, Harvey E. Beere, Ian Farrer, Paula Atkinson, Dave A. Ritchie. 2007-07-27. Quantisation of Hopping Magnetoresistance Prefactor in Strongly Correlated Two-Dimensional Electron Systems. https://doi.org/10.1016/j.physe.2007.08.099

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