Padé approximations of quantized-vortex solutions of the Gross–Pitaevskii equation. (21st June 2021)

• Record Type: Journal Article
• Authors: Chen, Weiru; Lan, Shanquan; Liu, Xiyi; Mo, Jiexiong; Xu, Xiaobao; Li, Guqiang
• Is Part Of: Communications in theoretical physics. Volume 73:Number 8(2021)
• Publication Date: 2021-06-21
• Subjects: Gross–Pitaevskii equation -- Padé approximation -- quantized-vortex solution; Physics -- Periodicals; 530.105
• DOI: 10.1088/1572-9494/abfe52
• Languages: English
• ISSNs: 0253-6102

Abstract

Abstract: Quantized vortices are important topological excitations in Bose–Einstein condensates. The Gross–Pitaevskii equation is a widely accepted theoretical tool. High accuracy quantized-vortex solutions are desirable in many numerical and analytical studies. We successfully derive the Padé approximate solutions for quantized vortices with winding numbers ω = 1, 2, 3, 4, 5, 6 in the context of the Gross–Pitaevskii equation for a uniform condensate. Compared with the numerical solutions, we find that (1) they approximate the entire solutions quite well from the core to infinity; (2) higher-order Padé approximate solutions have higher accuracy; (3) Padé approximate solutions for larger winding numbers have lower accuracy. The healing lengths of the quantized vortices are calculated and found to increase almost linearly with the winding number. Based on experiments performed with 87 Rb cold atoms, the healing lengths of quantized vortices and the number of particles within the healing lengths are calculated, and they may be checked by experiment. Our results show that the Gross–Pitaevskii equation is capable of describing the structure of quantized vortices and physics at length scales smaller than the healing length.