Renormalization group approach to the Fröhlich polaron model: application to impurity-BEC problem

F. Grusdt; Y. E. Shchadilova; A. N. Rubtsov; E. Demler

doi:10.1038/srep12124

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arXiv · 1410.2203

Renormalization group approach to the Fröhlich polaron model: application to impurity-BEC problem

F. Grusdt·Y. E. Shchadilova·A. N. Rubtsov·E. Demler

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Abstract

We develop a renormalization group approach for analyzing Fröhlich polarons and apply it to a problem of impurity atoms immersed in a Bose-Einstein condensate of ultra cold atoms. Polaron energies obtained by our method are in excellent agreement with recent diagrammatic Monte Carlo calculations for a wide range of interaction strengths. We calculate the effective mass of polarons and find a smooth crossover from weak to strong coupling regimes. Possible experimental tests of our results in current experiments with ultra cold atoms are discussed.

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F. Grusdt, Y. E. Shchadilova, A. N. Rubtsov, E. Demler. 2014-10-08. Renormalization group approach to the Fröhlich polaron model: application to impurity-BEC problem. https://doi.org/10.1038/srep12124

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