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

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

URL: http://arxiv.org/abs/2109.05607v2
Date: Thu, 23 Dec 2021 19:20:32 GMT
Title: Preparing exact eigenstates of the open XXZ chain on a quantum computer
Authors: John S. Van Dyke, Edwin Barnes, Sophia E. Economou, Rafael I. Nepomechie
Abstract summary: 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.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
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 $\binom{L}{M}\, 2^{M}\, M!$ terms, the algorithm requires $L+M^2+2M$ qubits.

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