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arXiv · 2405.05327

Higher Berry Connection for Matrix Product States

Shuhei Ohyama·Shinsei Ryu
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Abstract

In one spatial dimension, families of short-range entangled many-body quantum states, parameterized over some parameter space, can be topologically distinguished and classified by topological invariants built from the higher Berry phase -- a many-body generalization of the Berry phase. Previous works identified the underlying mathematical structure (the gerbe structure) and introduced a multi-wavefunction overlap, a generalization of the inner product in quantum mechanics, which allows for the extraction of the higher Berry phase and topological invariants. In this paper, building on these works, we introduce a connection, the higher Berry connection, for a family of parameterized Matrix Product States (MPS) over a parameter space. We demonstrate the use of our formula for simple non-trivial models.

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Shuhei Ohyama, Shinsei Ryu. 2024-05-08. Higher Berry Connection for Matrix Product States. https://arxiv.org/abs/2405.05327

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