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arXiv · 2008.11955

Non-unitary dynamics of Sachdev-Ye-Kitaev chain

Chunxiao Liu·Pengfei Zhang·Xiao Chen
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Abstract

We construct a series of one-dimensional non-unitary dynamics consisting of both unitary and imaginary evolutions based on the Sachdev-Ye-Kitaev model. Starting from a short-range entangled state, we analyze the entanglement dynamics using the path integral formalism in the large $N$ limit. Among all the results that we obtain, two of them are particularly interesting: (1) By varying the strength of the imaginary evolution, the interacting model exhibits a first order phase transition from the highly entangled volume law phase to an area law phase; (2) The one-dimensional free fermion model displays an extensive critical regime with emergent two-dimensional conformal symmetry.

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Chunxiao Liu, Pengfei Zhang, Xiao Chen. 2020-08-27. Non-unitary dynamics of Sachdev-Ye-Kitaev chain. https://doi.org/10.21468/scipostphys.10.2.048

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