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arXiv · 2302.14791

Magneto-exciton limit of quantum Hall breakdown in graphene

A. Schmitt·M. Rosticher·T. Taniguchi·K. Watanabe·G. Fève·J-M. Berroir·G. Ménard·C. Voisin·M. O. Goerbig·B. Plaçais·E. Baudin
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Abstract

One of the intrinsic drift velocity limit of the quantum Hall effect is the collective magneto-exciton (ME) instability. It has been demonstrated in bilayer graphene (BLG) using noise measurements. We reproduce this experiment in monolayer graphene (MLG), and show that the same mechanism carries a direct relativistic signature on the breakdown velocity. Based on theoretical calculations of MLG- and BLG-ME spectra, we show that Doppler-induced instabilities manifest for a ME phase velocity determined by a universal value of the ME conductivity, set by the Hall conductance.

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A. Schmitt, M. Rosticher, T. Taniguchi, K. Watanabe, G. Fève, J-M. Berroir, G. Ménard, C. Voisin, M. O. Goerbig, B. Plaçais, E. Baudin. 2023-02-28. Magneto-exciton limit of quantum Hall breakdown in graphene. https://doi.org/10.1103/physrevb.108.085438

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