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arXiv · 2406.19609

On the infrared cutoff for dipolar droplets

Liang-Jun He·Fabian Maucher·Yong-Chang Zhang
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Abstract

The beyond mean-field physics due to quantum fluctuations is often described by the Lee-Huang-Yang (LHY) correction, which can be approximately written as a simple analytical expression in terms of the mean-field employing local density approximation. This model has proven to be very successful in predicting the dynamics in dipolar Bose-Einstein condensates both qualitatively and quantitatively. Yet, a small deviation between experimental results and the theoretical prediction has been observed when comparing experiment and theory of the phase boundary of a free-space quantum droplet. For this reason, we revisit the theoretical description of quantum fluctuations in dipolar quantum gases. We study alternative cutoffs, compare them to experimental results and discuss limitations.

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Liang-Jun He, Fabian Maucher, Yong-Chang Zhang. 2024-06-28. On the infrared cutoff for dipolar droplets. https://arxiv.org/abs/2406.19609

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