发表机构
University Kaiserslautern-Landau; University of Birmingham; University of St. Andrews; Universidade Federal de São Carlos（凯泽斯劳滕-兰道大学; 伯明翰大学; 圣安德鲁斯大学; 圣卡洛斯联邦大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出一种分析方法，利用简谐势阱将光子玻色-爱因斯坦凝聚体的涡核尺寸正则化至实验可实现尺度，通过复格罗斯-皮塔耶夫斯基方程与投影优化方法建模，可区分封闭与开放耗散系统。
AI 中文摘要
量子化涡旋是超流性的标志。然而，在光子玻色-爱因斯坦凝聚体中，光子-光子相互作用极弱，以至于在均匀系统中，愈合长度超过了实验可实现的凝聚体自身尺寸。本文表明，简谐约束会将涡旋尺寸正则化至实验可实现的尺度，且这种外部约束与泵浦染料填充微腔的标准实验装置极为相似。我们通过复格罗斯-皮塔耶夫斯基方程对凝聚体进行建模，并应用新近提出的投影优化方法获得近似动力学单涡旋解；该方法将封闭系统的变分方法推广至开放耗散系统，且不假设凝聚体相位的特定形式。驱动耗散系统特有的径向光子流，基于增益与损耗的竞争给出了涡核尺寸的定义，该条件在物理基础上重现了封闭系统的启发式定义。后续线性稳定性分析显示，相互作用以及泵浦与损耗均可驱动系统进入不稳定状态，由此可从根本上区分封闭系统与开放耗散系统。
英文摘要
Quantized vortices are a hallmark of superfluidity. However, in a photon Bose--Einstein condensate, the photon-photon interaction is so weak that in a homogeneous system the healing length exceeds the experimentally achievable size of the condensate itself. Here we show that a harmonic confinement regularizes the vortex size to experimentally achievable scales. Moreover, such an external confinement closely resembles the standard experimental setup of a pumped dye-filled microcavity. We model the condensate via a complex Gross--Pitaevskii equation and obtain an approximate dynamical single-vortex solution by applying the recently proposed projection optimization method. The latter generalizes the variational approach of closed systems to open-dissipative systems without assuming a specific form for the condensate phase. The radial photon flow, which is characteristic for driven-dissipative systems, yields a definition of the vortex core size based on the competition of gain and loss. However, this condition reproduces the heuristic closed system definition now based on physical grounds. A subsequent linear stability analysis shows that interaction, as well as pumping and loss can drive the system to an unstable regime. In this way one can fundamentally distinguish between closed and open-dissipative systems.
