Lanczos algorithm for full-frequency GW calculations in real space

ORAL

Abstract

The GW approximation is a reliable and accurate method for modeling single-particle excitations. However, full-frequency GW calculations for large systems remain a computational challenge. We propose a method that reformulates the correlation part of GW self-energy as a resolvent matrix element, which can be effectively computed with Lanczos algorithm. The implementation of this method in NanoGW demonstrates high accuracy and efficiency, enabling us to study systems with a few hundred atoms on a workstation. In a recent benchmark calculation, we employed 20 GPU nodes for full-frequency GW quasiparticle energies of a silicon nanoparticle containing nearly 2,000 atoms.

* WG and JZ acknowledge support from National Natural Science Foundation of China (12104080, 91961204), XingLiaoYingCai Project of Liaoning province, China (XLYC1905014), GHfund A (2022201, gh-fund202202012538), and the Fundamental Research Funds for the Central Universities (DUT22LK04 and DUT22ZD103). ZT and JRC acknowledge support from a subaward from the Center for Computational Study of Excited-State Phenomena in Energy Materials at LBNL, which is funded by the U.S. DOE, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under contract No. DE-AC02-05CH11231, as part of the Computational Materials Sciences Program, and the Welch Foundation under Grant No. F-2094.

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Publication: Weiwei Gao, Zhao Tang, Jijun Zhao, and James R. Chelikowsky, Lanczos algorithm for full-frequency GW calculations in real space, in preparation.

Presenters

  • Zhao Tang

    The University of Texas at Austin

Authors

  • Zhao Tang

    The University of Texas at Austin

  • Weiwei Gao

    Dalian University of Technology

  • Jijun Zhao

    Dalian University of Technology

  • James R Chelikowsky

    University of Texas at Austin