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arXiv · 2205.06428

Angular-time evolution for the Affleck-Kennedy-Lieb-Tasaki chain and its edge-state dynamics

Koutaro Nakajima·Kouichi Okunishi
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Abstract

We study the angular-time evolution that is a parameter-time evolution defined by the entanglement Hamiltonian for the bipartitioned ground state of the Affleck-Kennedy-Lieb-Tasaki (AKLT) chain with the open boundary. In particular, we analytically calculate angular-time spin correlation functions $\langle S_n^α(τ)S_n^α(0)\rangle$ with $α= x,y,z$, using the matrix-product-state (MPS) representation of the valence-bond-solid state with edges. We also investigate how the angular-time evolution operator can be represented in the physical spin space with the use of gauge transformation for the MPS. We then discuss the physical interpretation of the angular-time evolution in the AKLT chain.

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BibTeXRIS

Koutaro Nakajima, Kouichi Okunishi. 2022-10-11. Angular-time evolution for the Affleck-Kennedy-Lieb-Tasaki chain and its edge-state dynamics. https://doi.org/10.1103/physrevb.106.134304

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