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arXiv · 1408.3014

Degeneracy doubling and sublattice polarization in strain-induced pseudo-Landau levels

Charles Poli·Jake Arkinstall·Henning Schomerus
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Abstract

The degeneracy and spatial support of pseudo-Landau levels (pLLs) in strained honeycomb lattices systematically depends on the geometry -- for instance, in hexagonal and rectangular flakes the 0th pLL displays a twofold increased degeneracy, while the characteristic sublattice polarization of the 0th pLL is only fully realized in a zigzag-terminated triangle. These features are dictated by algebraic constraints in the atomistic theory, and signify a departure from the standard picture in which all qualitative differences between pLLs and Landau levels induced by a magnetic field trace back to the valley-antisymmetry of the pseudomagnetic field.

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Charles Poli, Jake Arkinstall, Henning Schomerus. 2014-08-13. Degeneracy doubling and sublattice polarization in strain-induced pseudo-Landau levels. https://doi.org/10.1103/physrevb.90.155418

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