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arXiv · 1809.08990

Infrared Problem in Cold Atom Quantum Physisorption on 2D Materials

Sanghita Sengupta·Dennis P. Clougherty
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Abstract

Results from four different approximations to the phonon-assisted quantum adsorption rate for cold atoms on a 2D material are compared and contrasted: (1) a loop expansion (LE) based on the atom-phonon coupling, (2) non-crossing approximation (NCA), (3) independent boson model approximation (IBMA), and (4) a leading-order soft-phonon resummation method (SPR). We conclude that, of the four approximations considered, only the SPR method gives a divergence-free result in the large membrane regime at finite temperature. The other three methods give an adsorption rate that diverges in the limit of an infinite surface.

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Sanghita Sengupta, Dennis P. Clougherty. 2018-09-24. Infrared Problem in Cold Atom Quantum Physisorption on 2D Materials. https://doi.org/10.1088/1742-6596/1148/1/012007

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