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DOE OSTI · 2927986

Fermionic Isometric Tensor Network States in Two Dimensions

Dai, Zhehao [University of California, Berkeley, CA (United States); University of Pittsburgh, PA (United States)] (ORCID:0000000237895683)·Wu, Yantao [RIKEN iTHEMS, Saitama (Japan); University of California, Berkeley, CA (United States)] (ORCID:0000000323609647)·Wang, Taige [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017227915X)·Zaletel, Michael P. [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]
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Abstract

We generalize isometric tensor network states to fermionic systems, paving the way for efficient adaptations of 1D tensor network algorithms to 2D fermionic systems. As the first application of this formalism, we developed and benchmarked a time-evolving block-decimation (TEBD) algorithm for real-time and imaginary-time evolution. The imaginary-time evolution produces ground-state energies for gapped systems, systems with a Dirac point, and systems with gapless edge modes to good accuracy. Here, the real-time TEBD captures the scattering of two fermions and the chiral edge dynamics on the boundary of a Chern insulator.

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2-dimensional systems75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYLattice models in condensed matterTensor network methodslattice models in condensed mattertensor network methods

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Dai, Zhehao [University of California, Berkeley, CA (United States); University of Pittsburgh, PA (United States)] (ORCID:0000000237895683), Wu, Yantao [RIKEN iTHEMS, Saitama (Japan); University of California, Berkeley, CA (United States)] (ORCID:0000000323609647), Wang, Taige [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017227915X), Zaletel, Michael P. [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]. 2025-01-14. Fermionic Isometric Tensor Network States in Two Dimensions. https://doi.org/10.1103/physrevlett.134.026502

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