Improving the efficiency of open-quantum-system simulations using matrix product states in the interaction picture

Journal Article (Journal Article)

Modeling open quantum systems-quantum systems coupled to a bath-is of value in condensed-matter theory, cavity quantum electrodynamics, nanosciences, and biophysics. The real-time simulation of open quantum systems was advanced significantly by the recent development of chain mapping techniques and the use of matrix product states that exploit the intrinsic entanglement structure in open quantum systems. The computational cost of simulating open quantum systems, however, remains high when the bath is excited to high-lying quantum states. We develop an approach to reduce the computational costs in such cases. The interaction representation for the open quantum system is used to distribute excitations among the bath degrees of freedom so that the occupation of each bath oscillator is ensured to be low. The interaction picture also causes the matrix dimensions to be much smaller in a matrix product state of a chain-mapped open quantum system than in the Schrödinger picture. Using the interaction representation accelerates the calculations by one to two orders of magnitude over the existing matrix-product-state method. In the regime of strong system-bath coupling and high temperatures, the speedup can be as large as three orders of magnitude. The approach developed here is especially promising to simulate the dynamics of open quantum systems in high-temperature and strong-coupling regimes.

Full Text

Duke Authors

Cited Authors

  • Liu, KT; Beratan, DN; Zhang, P

Published Date

  • March 1, 2022

Published In

Volume / Issue

  • 105 / 3

Electronic International Standard Serial Number (EISSN)

  • 2469-9934

International Standard Serial Number (ISSN)

  • 2469-9926

Digital Object Identifier (DOI)

  • 10.1103/PhysRevA.105.032406

Citation Source

  • Scopus