Correlation dynamics of finite fermion systems

H. Flocard

Stephan Haas

Hao Shi, Yuan-Yao He, Shiwei Zhang

Joel Frederick Corney, P. D. Drummond

We present a phase-space method for fermionic systems, which enables simulations of the dynamics and thermal equilibrium states of many-body quantum systems from first principles. As examples, we calculate finite-temperature correlation functions.

Masatoshi Imada

Przemysław Bieniek, Timo Gräßer, Götz Silvester Uhrig

In recent years, a method for computing spin dynamics at infinite temperature (spinDMFT) was developed. It utilizes the ideas of dynamical mean-field theory for fermions: single-site approximation and a self-consistency condition to approximate time-dependent spin correlations. In this work, we develop a crucial extension of the method to systems at finite temperature, able to compute imaginary-time correlations and thermodynamical quantities. We benchmark the method by comparison to results in finite-size systems, obtaining very good agreement with correlations in a random-coupling system, good agreement for a ferromagnetic system and large discrepancies in the case of an antiferromagnet. We note the appearance of ferromagnetic order in the method. We discuss possible extensions and potential applications of the approach.