Thermal Pure Quantum Matrix Product States
Abstract
We propose a way to construct thermal pure quantum matrix product state (TPQMPS) that can simulate finite temperature quantum many body systems with a minimal numerical cost comparable to the matrix product algorithm for the ground state in onedimensional systems. Taking a random matrix product state with auxiliary sites attached to the edges of the system, one can anneal it down to lowest temperature, keeping the effective bond dimension of the matrix almost uniform, which will generate a flat profile of the entanglement that looks nothing like a Page curve. The finite temperature physical quantities of the transverse Ising and the spin1/2 Heisenberg chains evaluated by the TPQMPS show excellent agreement even for bond dimension $\sim 1020$ with those of the quantum Monte Carlo calculation and the exact solutions.
 Publication:

arXiv eprints
 Pub Date:
 May 2020
 arXiv:
 arXiv:2005.06829
 Bibcode:
 2020arXiv200506829I
 Keywords:

 Condensed Matter  Strongly Correlated Electrons
 EPrint:
 5 pages, 3 figures