Entanglement spectrum in one-dimensional systems

Pasquale Calabrese; Alexandre Lefevre

doi:10.1103/physreva.78.032329

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arXiv · 0806.3059

Entanglement spectrum in one-dimensional systems

Pasquale Calabrese·Alexandre Lefevre

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Abstract

We derive the distribution of eigenvalues of the reduced density matrix of a block of length l in a one-dimensional system in the scaling regime. The resulting "entanglement spectrum" is described by a universal scaling function depending only on the central charge of the underlying conformal field theory. This prediction is checked against exact results for the XX chain. We also show how the entanglement gap closes when l is large.

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Pasquale Calabrese, Alexandre Lefevre. 2008-06-18. Entanglement spectrum in one-dimensional systems. https://doi.org/10.1103/physreva.78.032329

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