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arXiv · 0707.4259

Fermi-Polaron: Diagrammatic Monte Carlo for Divergent Sign-Alternating Series

Nikolay Prokof'ev·Boris Svistunov
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Abstract

Diagrammatic Monte Carlo approach is applied to a problem of a single spin-down fermion resonantly interacting with the sea of ideal spin-up fermions. On one hand, we develop a generic, sign-problem tolerant, method of exact numerical solution of polaron-type models. On the other hand, our solution is important for understanding the phase diagram and properties of the BCS-BEC crossover in the strongly imbalanced regime. This is the first, and possibly characteristic, example of how the Monte Carlo approach can be applied to a divergent sign-alternating diagrammatic series.

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Nikolay Prokof'ev, Boris Svistunov. 2007-09-24. Fermi-Polaron: Diagrammatic Monte Carlo for Divergent Sign-Alternating Series. https://doi.org/10.1103/physrevb.77.020408

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