arXiv:2109.05607 · Journal of Physics A Mathematical and Theoretical

Preparing exact eigenstates of the open XXZ chain on a quantum computer

John S. Van Dyke, Edwin Barnes, Sophia E. Economou, Rafael I. Nepomechie

Published Dec 23, 2021• 27 citations

Abstract

Abstract The open spin-1/2 XXZ spin chain with diagonal boundary magnetic fields is the paradigmatic example of a quantum integrable model with open boundary conditions. We formulate a quantum algorithm for preparing Bethe states of this model, corresponding to real solutions of the Bethe equations. The algorithm is probabilistic, with a success probability that decreases with the number of down spins. For a Bethe state of L spins with M down spins, which contains a total of L M 2 M M ! terms, the algorithm requires L + M 2 + 2 M qubits.

DOI: 10.1088/1751-8121/ac4640

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