The TRIQS arbirary X-Crossing Approximation impurity solver (triqs_xca)

ORAL

Abstract

The triqs_xca solver is the latest quantum impurity solver addition to the Toolbox for Research on Interacting Quantum Systems (TRIQS) based on the bold hybridization expansion, a.k.a. the X:th order Crossing Approximation (XCA). Using the sum-of-exponentials trick we acheive parametrically better computational complexity compared to direct integration and the Discrete Lehmann Representation (DLR) is employed for fast convolutions as well as for representing response functions. The solver is open source and distributed as part of the TRIQS project, see github.com/TRIQS/xca.

*We acknowledge financial support from; the Swedish Research Council (Vetenskapsrådet, VR) grant number 2024-04652, the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 854843-FASTCORR), and the Simons Foundation's Center for Computational Quantum Physics at the Flatiron Institute.

Publication: J. Kaye, Z. Huang, H.U.R. Strand, D. Golež, Phys. Rev. X 14, 031034 (2024)
Z. Huang, D. Golež, H.U.R. Strand, J. Kaye, arXiv:2503.19727 (accepted in SciPost)

Presenters

  • Hugo U. R. Strand

    • Örebro University

Authors

  • Hugo U. R. Strand

    • Örebro University
  • Francisco P Rilloraza

    • New York University
    • New York University (NYU)
  • Zhen Huang

    • University of California, Berkeley
  • Nils Wentzell

    • Flatiron Institute, Simons Foundation
  • Denis Golez

    • Jožef Stefan Institute
    • Jozef Stefan Institute
    • Jozef Stefan Institute, University of Ljubljana
  • Jason Kaye

    • Simons Foundation (Flatiron Institute)