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arXiv · 2009.04488

Variational Preparation of the Sachdev-Ye-Kitaev Thermofield Double

Vincent Paul Su
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Abstract

We provide an algorithm for preparing the thermofield double (TFD) state of the Sachdev-Ye-Kitaev model without the need for an auxiliary bath. Following previous work, the TFD can be cast as the approximate ground state of a Hamiltonian, $H_{\text{TFD}}$. Using variational quantum circuits, we propose and implement a gradient-based algorithm for learning parameters that find this ground state, an application of the variational quantum eigensolver. Concretely, we find quantum circuits that prepare the ground state of $H_{\text{TFD}}$ for the $q=4$ SYK model up to $N=12$.

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Vincent Paul Su. 2020-09-09. Variational Preparation of the Sachdev-Ye-Kitaev Thermofield Double. https://doi.org/10.1103/physreva.104.012427

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