Imaginary-time matrix product state impurity solver for dynamical mean-field theory
Abstract
We present a new impurity solver for dynamical mean-field theory based on imaginary-time evolution of matrix product states. This converges the self-consistency loop on the imaginary-frequency axis and obtains real-frequency information in a final real-time evolution. Relative to computations on the real-frequency axis, required bath sizes are much smaller and less entanglement is generated, so much larger systems can be studied. The power of the method is demonstrated by solutions of a three band model in the single and two-site dynamical mean-field approximation. Technical issues are discussed, including details of the method, efficiency as compared to other matrix product state based impurity solvers, bath construction and its relation to real-frequency computations and the analytic continuation problem of quantum Monte Carlo, the choice of basis in dynamical cluster approximation, and perspectives for off-diagonal hybridization functions.
Cite
@article{arxiv.1507.08650,
title = {Imaginary-time matrix product state impurity solver for dynamical mean-field theory},
author = {F. Alexander Wolf and Ara Go and Ian P. McCulloch and Andrew J. Millis and Ulrich Schollwöck},
journal= {arXiv preprint arXiv:1507.08650},
year = {2015}
}
Comments
8 pages + 4 pages appendix, 9 figures