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arXiv · 1909.12017

Valley polarization braiding in strained graphene

D. Faria·C. León·L. R. F. Lima·A. Latgé·N. Sandler
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Abstract

Previous works on deformed graphene predict the existence of valley-polarized states, however, optimal conditions for their detection remain challenging. We show that in the quantum Hall regime, edge-like states in strained regions can be isolated in energy within Landau gaps. We identify precise conditions for new conducting edges-like states to be valley polarized, with the flexibility of positioning them at chosen locations in the system. A map of local density of states as a function of energy and position reveals a unique braid pattern that serves as a fingerprint to identify valley polarization.

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D. Faria, C. León, L. R. F. Lima, A. Latgé, N. Sandler. 2019-09-26. Valley polarization braiding in strained graphene. https://doi.org/10.1103/physrevb.101.081410

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