Efficient Quantum Simulation for Thermodynamics of Infinite-size Many-body Systems in Arbitrary Dimensions

TL;DR

This paper introduces quantum entanglement simulators (QES) that efficiently replicate the thermodynamics of infinite-size quantum many-body systems across various dimensions using small, optimized models, enabling exploration of complex phenomena.

Contribution

The work presents a novel QES approach that uses tensor network methods to simulate infinite quantum systems with small, optimized models, extending across multiple dimensions.

Findings

QES accurately reproduces finite-temperature phenomena in quantum spin liquids.

QES captures phase transitions and low-temperature physics in 2D and 3D antiferromagnets.

QES models effectively simulate topological system crossovers.

Abstract

In this work we propose to simulate many-body thermodynamics of infinite-size quantum lattice models in one, two, and three dimensions, in terms of few-body models of only O(10) sites, which we coin as quantum entanglement simulators (QES's). The QES is described by a temperature-independent Hamiltonian, with the boundary interactions optimized by the tensor network methods to mimic the entanglement between the bulk and environment in a finite-size canonical ensemble. The reduced density matrix of the physical bulk then gives that of the infinite-size canonical ensemble under interest. We show that the QES can, for instance, accurately simulate varieties of many-body phenomena, including finite-temperature crossover and algebraic excitations of the one-dimensional spin liquid, the phase transitions and low-temperature physics of the two- and three-dimensional antiferromagnets, and the crossovers of the two-dimensional topological system. Our work provides an efficient way to explore the thermodynamics of intractable quantum many-body systems with easily accessible systems.