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Visualizing quasiparticles from quantum entanglement for general one-dimensional phases

Wybo, Elisabeth·Pollmann, Frank·Sondhi, S. L.·You, Yizhi
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Abstract

In this work, we present a quantum information framework for the entanglement behavior of the low-energy quasiparticle (QP) excitations in various quantum phases in one-dimensional (1D) systems. We first establish an exact correspondence between the correlation matrix and the QP entanglement Hamiltonian for free fermions and find an extended in-gap state in the QP entanglement Hamiltonian as a consequence of the position uncertainty of the QP. A more general understanding of such an in-gap state can be extended to a Kramers theorem for the QP entanglement Hamiltonian, which also applies to strongly interacting systems. Further, we present a set of ubiquitous entanglement spectrum features, dubbed entanglement fragmentation, conditional mutual information, and measurement-induced nonlocal entanglement for QPs in 1D symmetry protected topological phases. Our result thus provides another framework to identify different phases of matter in terms of their QP entanglement.

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1-dimensional spin chains75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYmaterials sciencephysicsquantum entanglementquantum phase transitionsquasiparticles & collective excitationssymmetry protected topological statestensor network methods

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Wybo, Elisabeth, Pollmann, Frank, Sondhi, S. L., You, Yizhi. 2021-03-12. Visualizing quasiparticles from quantum entanglement for general one-dimensional phases. https://doi.org/10.1103/physrevb.103.115120

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