Variational study of U(1) and SU(2) lattice gauge theories with Gaussian states in 1+1 dimensions

• Main Authors: Sala, P, Shi, T, Kühn, S, Bañuls, M. C, Demler, E, Cirac, J. I
• Format: Journal Article
• Language: English
• Published: 26-09-2018
• Subjects: Physics - High Energy Physics - Lattice; Physics - Quantum Physics; Physics - Strongly Correlated Electrons
• DOI: 10.48550/arxiv.1805.05190

Phys. Rev. D 98, 034505 (2018) We introduce a method to investigate the static and dynamic properties of
both Abelian and non-Abelian lattice gauge models in 1+1 dimensions.
Specifically, we identify a set of transformations that disentangle different
degrees of freedom, and apply a simple Gaussian variational ansatz to the
resulting Hamiltonian. To demonstrate the suitability of the method, we analyze
both static and dynamic aspects of string breaking for the U(1) and SU(2) gauge
models. We benchmark our results against tensor network simulations and observe
excellent agreement, although the number of variational parameters in the
Gaussian ansatz is much smaller.