Related papers: Spectral Gaps via Imaginary Time

Spectral Gaps via Imaginary Time

URL: http://arxiv.org/abs/2303.02124v1
Date: Fri, 3 Mar 2023 18:08:14 GMT
Title: Spectral Gaps via Imaginary Time
Authors: Jacob M. Leamer, Alicia B. Magann, Andrew D. Baczewski, Gerard McCaul, Denys I. Bondar
Abstract summary: We present an approach for evaluating the spectral gap of a Hamiltonian from a simple ratio of two expectation values. In principle, the only requirement is that the initial state is supported on both the ground and first excited states.
Score: 0.0
License: http://creativecommons.org/licenses/by/4.0/
Abstract: The spectral gap occupies a role of central importance in many open problems in physics. We present an approach for evaluating the spectral gap of a Hamiltonian from a simple ratio of two expectation values, both of which are evaluated using a quantum state that is evolved in imaginary time. In principle, the only requirement is that the initial state is supported on both the ground and first excited states. We demonstrate this approach for the Fermi-Hubbard and transverse field Ising models through numerical simulation.

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