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arXiv · 1508.05829

Entanglement spectrum and entangled modes of highly excited states in random XX spin chains

Mohammad Pouranvari·Kun Yang
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Abstract

We examine the real space renormalization group method of finding \textit{excited eigenstate} (RSRG-X) of the XX spin-1/2 chain, from entanglement perspectives. Eigenmodes of entanglement Hamiltonian, especially the maximally entangled mode and corresponding entanglement energies are studied and compared with predictions of RSRG-X. Our numerical results demonstrate the accuracy of the RSRG-X method in the strong disorder limit, and quantify its error when applied to weak disorder regime. Overall, our results validate the RSRG-X method qualitatively, but also show that its accuracy decreases with increasing temperature.

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Mohammad Pouranvari, Kun Yang. 2016-01-12. Entanglement spectrum and entangled modes of highly excited states in random XX spin chains. https://doi.org/10.1103/physrevb.92.245134

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