Thermal coupled cluster theory for SU(2) systems

Article

关键词: BODY APPROXIMATION METHODS;    QUANTUM MONTE-CARLO;    FINITE-TEMPERATURE;    SOLVABLE MODEL;    PERTURBATION-THEORY;    FIELD-DYNAMICS;    ISING-MODEL;    VALIDITY;    HEISENBERG;    EXPANSION;   

DOI  :  10.1103/PhysRevB.105.045125

来源: SCIE

【 摘 要 】

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 thermofieldinspired thermal CC for SU(2) systems. 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.

【 授权许可】

Free