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arXiv · 1403.1039

Position momentum Duality in the Entanglement Spectrum of Free Fermions

Ching Hua Lee·Peng Ye·Xiao-Liang Qi
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Abstract

We propose an exact equivalence between the entanglement spectra of two completely different free-fermion systems at zero temperature. This equivalence follows from a position-momentum duality where the physical roles of the occupied band and real space projectors are exchanged. We examine the physical consequences of this duality in multi-band models, and as an example also physically motivate the equivalence of the entanglement spectrum of a real space partitioned two-band topological insulator with that of a bilayer Fermi gas with an interlayer partition. This duality has an interesting relation with the Wannier Spectrum in the high-temperature limit, and can also be extended to other basis-independent physical quantities like particle-number fluctuations.

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Ching Hua Lee, Peng Ye, Xiao-Liang Qi. 2014-09-03. Position momentum Duality in the Entanglement Spectrum of Free Fermions. https://doi.org/10.1088/1742-5468%2F2014%2F10%2Fp10023

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