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arXiv · 2412.01902

Precision study of the massive Schwinger model near quantum criticality

Erick Arguello Cruz·Grigory Tarnopolsky·Yuan Xin
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Abstract

We perform a numerical analysis of the massive Schwinger model in the presence of a background electric field. Using the Density Matrix Renormalization Group (DMRG) approach, we efficiently compute the spectrum of the Schwinger model on a staggered lattice with up to 3000 qubits. As a result, we achieve a precise computation of the critical mass of the massive Schwinger model to five digits using four different 'criticality criteria', observing perfect agreement among them. Additionally, we discuss the effect of a four-fermion operator deformation of the Schwinger model and compute the critical mass for various values of the deformation parameter.

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Erick Arguello Cruz, Grigory Tarnopolsky, Yuan Xin. 2024-12-02. Precision study of the massive Schwinger model near quantum criticality. https://arxiv.org/abs/2412.01902

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