Renormalized dual basis for scalable simulations of 2+1D compact quantum electrodynamics
Phys. Rev. D 113, 074518 – Published 22 April, 2026
DOI: https://doi.org/10.1103/bf5k-xvw8
Abstract
The classical and quantum simulation of lattice gauge theories (LGTs) with Lie groups is hindered by the infinite-dimensional Hilbert space of gauge degrees of freedom. In a recent work [P. Fontana et al., Efficient finite-resource formulation of non-Abelian lattice gauge theories beyond one dimension, Phys. Rev. X 15, 031065 (2025)], we introduced a new truncation scheme—here renamed as the renormalized dual basis (RDB)—based on the resolution of the single-plaquette problem, and demonstrated its performance for SU(2) LGTs. In this paper, we apply the RDB to compact quantum electrodynamics (in three spacetime dimensions (2+1D). We variationally determine the ground state of the theory for small lattices with periodic (for pure gauge) and open (in presence of fermionic matter) boundary conditions, achieving improved precision for the plaquette operator compared to previous approaches. By leveraging tensor networks, we extend the study to larger lattices and demonstrate the scalability of the method. Overall, we show that the RDB provides an efficient description across all coupling regimes.
