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Multiorbital dynamical mean-field theory with a complex-time solver

Yang Yu1, Lei Zhang1, Emanuel Gull1,2, Xiaodong Cao3,4,*, and Xinyang Dong5,†

  • *Contact author: xdcao@ustc.edu.cn
  • †Contact author: dongxy@iphy.ac.cn
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Phys. Rev. Research 8, 023142 – Published 11 May, 2026

DOI: https://doi.org/10.1103/yqv4-4vjx

Abstract

We present the combination of a complex-time tensor-network impurity solver with an analytic continuation scheme based on exponential fitting as an efficient framework for single and multiorbital dynamical mean-field calculations. By performing time evolution along a complex-time contour, the approach balances computational cost with the difficulty of spectral recovery, offering greater flexibility than methods confined to the real or imaginary axis. By complementing the complex-time evolution with an exponential fitting scheme, we faithfully extract real-time information at negligible cost. The resulting method obtains high-resolution spectra at a significantly lower computational cost than real-time evolution, offering a promising tool for ab initio studies of strongly correlated materials.

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Phys. Rev. Research 8, 023142– Published 11 May, 2026
  • Received 6 January 2026
  • Accepted 2 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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