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arXiv · 1510.03506

Measurement of Topological Berry Phase in Highly Disordered Graphene

K. Bennaceur·J. Guillemette·P. L. Lévesque·N. Cottenye·F. Mahvash·N. Hemsworth·A. Kumar·Y. Murata·S. Heun·M. O. Goerbig·C. Proust·M. Siaj·R. Martel·G. Gervais·T. Szkopek
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Abstract

We have observed the quantum Hall effect (QHE) and Shubnikov-de Haas (SdH) oscillations in highly disordered graphene at magnetic fields up to 65 T. Disorder was introduced by hydrogenation of graphene up to a ratio H/C $\approx 0.1\%$. The analysis of SdH oscillations and QHE indicates that the topological part of the Berry phase, proportional to the pseudo-spin winding number, is robust against introduction of disorder by hydrogenation in large scale graphene.

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K. Bennaceur, J. Guillemette, P. L. Lévesque, N. Cottenye, F. Mahvash, N. Hemsworth, A. Kumar, Y. Murata, S. Heun, M. O. Goerbig, C. Proust, M. Siaj, R. Martel, G. Gervais, T. Szkopek. 2015-10-13. Measurement of Topological Berry Phase in Highly Disordered Graphene. https://doi.org/10.1103/physrevb.92.125410

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