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arXiv · 1706.02975

Quantum Monte Carlo solution of the dynamical mean field equations in real time

Qiaoyuan Dong·Igor Krivenko·Joseph Kleinhenz·Andrey E. Antipov·Guy Cohen·Emanuel Gull
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Abstract

We present real-time inchworm quantum Monte Carlo results for single-site dynamical mean field theory on an infinite coordination number Bethe lattice. Our numerically exact results are obtained on the L-shaped Keldysh contour and, being evaluated in real-time, avoid the analytic continuation issues typically encountered in Monte Carlo calculations. Our results show that inchworm Monte Carlo methods have now reached a state where they can be used as dynamical mean field impurity solvers and the dynamical sign problem can be overcome. As non-equilibrium problems can be simulated at the same cost, we envisage the main use of these methods as dynamical mean field solvers for time-dependent problems far from equilibrium.

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Qiaoyuan Dong, Igor Krivenko, Joseph Kleinhenz, Andrey E. Antipov, Guy Cohen, Emanuel Gull. 2017-06-09. Quantum Monte Carlo solution of the dynamical mean field equations in real time. https://doi.org/10.1103/physrevb.96.155126

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