美国史蒂文斯理工学院曲春雷小组的一项最新研究提出了谐波捕获二元玻色-爱因斯坦凝聚中的参量激发。相关论文于2025年12月1日发表于国际顶尖学术期刊《物理评论 A》杂志上。

该课题组人员研究了一个谐波捕获的双组分玻色-爱因斯坦凝聚中的参量激发和模式形成。该研究团队假设冷凝物处于混相，但接近混相-不混相的相变，其中总密度和自旋密度激发是解耦的。通过周期性调制原子散射长度，可以在密度和自旋通道中产生法拉第模式。在细长凝聚体中，自旋通道中的模式对应于一维驻波，其中两个分量表现出非相密度振荡，其中调制频率和振荡周期与自旋声的速度有关。自旋模式充分发展后，系统迅速进入非线性失稳状态。对于饼状凝聚体，二维法拉第模式产生了一个有趣的-折叠旋转对称。随着调制频率的增大，沿径向和角方向的节点数增加。课题组人员还比较了不同调制方案产生的自旋法拉第模式的增长率，这是目前实验可以获得的。

附：英文原文

Title: Parametric excitations in a harmonically trapped binary Bose-Einstein condensate

Author: Meiling Wang, Juan Wang, Yan Li, Franco Dalfovo, Chunlei Qu

Issue&Volume: 2025/12/01

Abstract: We investigate parametric excitation and pattern formation in a harmonically trapped two-component Bose-Einstein condensate. We assume the condensate to be in the miscible phase, but near the miscible-immiscible phase transition, where total-density and spin-density excitations are decoupled. By periodically modulating the atomic scattering lengths, Faraday patterns can be generated in both density and spin channels. In an elongated condensate, the pattern in the spin channel corresponds to a one-dimensional standing wave with the two components exhibiting an out-of-phase density oscillation, where the modulation frequency and the oscillation period are related to the velocity of the spin sound. After the spin pattern is fully developed, the system quickly enters a nonlinear destabilization regime. For a pancake-shaped condensate, a two-dimensional Faraday pattern is generated with an interesting -fold rotational symmetry. The number of nodes along the radial and angular directions increases with larger modulation frequencies. We also compare the growth rates of spin Faraday patterns generated with different modulation protocols, which are accessible to current experiments.

DOI: 10.1103/rj7v-q9gy

Source: https://journals.aps.org/pra/abstract/10.1103/rj7v-q9gy