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arXiv · 1610.03696

Inverse participation ratio and localization in topological insulator phase transitions

M. Calixto·E. Romera
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Abstract

Fluctuations of Hamiltonian eigenfunctions, measured by the inverse participation ratio (IPR), turn out to characterize topological-band insulator transitions occurring in 2D Dirac materials like silicene, which is isostructural with graphene but with a strong spin-orbit interaction. Using monotonic properties of the IPR, as a function of a perpendicular electric field (which provides a tunable band gap), we define topological-like quantum numbers that take different values in the topological-insulator and band-insulator phases.

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M. Calixto, E. Romera. 2016-10-12. Inverse participation ratio and localization in topological insulator phase transitions. https://doi.org/10.1088/1742-5468%2F2015%2F06%2Fp06029

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