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arXiv · 2110.13046

Quantum Computation of Phase Transition in the Massive Schwinger Model

Shane Thompson·George Siopsis
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Abstract

As pointed out by Coleman, physical quantities in the Schwinger model depend on a parameter $\theta$ that determines the background electric field. There is a phase transition for $\theta = \pi$ only. We develop a momentum space formalism on a lattice and use it to perform a quantum computation of the critical point of this phase transition on the NISQ device IMB Q Lima. After error mitigation, our results give strong indication of the existence of a critical point at $m/e\simeq 0.32$, where $m$ is the bare fermion mass and $e$ is the coupling strength, in good agreement with the classical numerical result $m/e \simeq 0.3335$.

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Shane Thompson, George Siopsis. 2021-10-25. Quantum Computation of Phase Transition in the Massive Schwinger Model. https://doi.org/10.1088/2058-9565%2Fac5f5a

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