近日，佛山大学黎永耀团队研究了二元玻色-爱因斯坦凝聚体中的细长涡旋量子液滴。这一研究成果于2025年7月28日发表在《物理评论A》杂志上。

嵌入单一和多重涡度的细长量子液滴（QDs）的稳定性是一个以前没有解决的问题。

在这项工作中，研究组提出了一个解决方案，它依赖于二元玻色-爱因斯坦凝聚体中种间散射长度的空间调制的主题，以二维轴对称高斯矩阵的形式，通过光学费什巴赫共振形成。相应的有效非线性捕获势支持涡度S=0的完全稳定的拉长量子点和S=1,2,3,4的部分稳定拉长量子点族（其他非线性系统不保持≥2的涡滴稳定性）。

研究组系统地分析了高斯调制的振幅和宽度以及原子总数对量子点形状和稳定性的影响，并对一些影响进行了解析解释。S=1的相同量子点之间的碰撞沿中心轴方向相反，导致它们合并成具有相同涡度的更长的呼吸量子点，而S=±1的量子点之间的碰撞是准弹性的。移动调制轮廓能够绝热旋转被捕获的细长量子点。在机器人进动的陀螺状态下对矢量QD集施加力矩，实现了宏观的自旋-轨道耦合效应。

附：英文原文

Title: Elongated vortex quantum droplets in binary Bose-Einstein condensates

Author: Guilong Li, Zibin Zhao, Rui Zhang, Zhaopin Chen, Bin Liu, Boris A. Malomed, Yongyao Li

Issue&Volume: 2025/07/28

Abstract: Stability of elongated (“slender”) quantum droplets (QDs) with embedded unitary and multiple vorticity is a problem that was not solved previously. In this work, we propose a solution which relies upon the use of the spatial modulation of the interspecies scattering length in the binary Bose-Einstein condensates, in the form of a two-dimensional axisymmetric Gaussian, shaped by means of the optical Feshbach resonance. The corresponding effective nonlinear trapping potential supports completely stable elongated QDs with vorticity S=0 and partly stable families of elongated QDs with S=1,2,3,4 (other nonlinear systems do not maintain stability of vortex droplets with ≥2). We systematically analyze effects of the amplitude and width of the Gaussian modulation, as well as the total number of atoms, on the shape and stability of the QDs, some effects being explained analytically. Collisions between identical QDs with S=1 moving in opposite directions along the central axis leads to their merger into still more elongated breathing QDs with the same vorticity, while collisions between QDs with S=±1 are quasielastic. Moving modulation profiles are able to adiabatically rotate the trapped elongated QDs. Application of a torque to the vector QD sets in the gyroscopic regime of robust precession, which realizes a macroscopic spin-orbit-coupling effect.

DOI: 10.1103/771t-rkdj

Source: https://journals.aps.org/pra/abstract/10.1103/771t-rkdj