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arXiv · 1911.00653

Non-local Order Parameters and Quantum Entanglement for Fermionic Topological Field Theories

Kansei Inamura·Ryohei Kobayashi·Shinsei Ryu
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Abstract

We study quantized non-local order parameters, constructed by using partial time-reversal and partial reflection, for fermionic topological phases of matter in one spatial dimension protected by an orientation reversing symmetry, using topological quantum field theories (TQFTs). By formulating the order parameters in the Hilbert space of state sum TQFT, we establish the connection between the quantized non-local order parameters and the underlying field theory, clarifying the nature of the order parameters as topological invariants. We also formulate several entanglement measures including the entanglement negativity on state sum spin TQFT, and describe the exact correspondence of the entanglement measures to path integrals on a closed surface equipped with a specific spin structure.

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Kansei Inamura, Ryohei Kobayashi, Shinsei Ryu. 2019-11-02. Non-local Order Parameters and Quantum Entanglement for Fermionic Topological Field Theories. https://doi.org/10.1007/jhep01(2020)121

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