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DOE OSTI · 1842778

Thermal coupled cluster theory for SU(2) systems

Harsha, Gaurav·Xu, Yi·Henderson, Thomas M.·Scuseria, Gustavo E.
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Abstract

Coupled cluster (CC) has established itself as a powerful theory to study correlated quantum many-body systems. Finite-temperature generalizations of CC theory have attracted considerable interest and have been shown to work as nicely as the ground-state theory. However, most of these recent developments address only fermionic or bosonic systems. The distinct structure of the su(2) algebra requires the development of a similar thermal CC theory for spin degrees of freedom. In this paper, we provide a formulation of our thermofield-inspired thermal CC for SU(2) systems. Here, we apply the thermal CC to the Lipkin-Meshkov-Glick system as well as the one-dimensional transverse field Ising model as benchmark applications to highlight the accuracy of thermal CC in the study of finite-temperature phase diagrams in SU(2) systems.

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BibTeXRIS

Harsha, Gaurav, Xu, Yi, Henderson, Thomas M., Scuseria, Gustavo E.. 2022-01-19. Thermal coupled cluster theory for SU(2) systems. https://doi.org/10.1103/physrevb.105.045125

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