论文标题
量子涡流的重新连接是由捕获的颗粒介导的
Quantum vortex reconnections mediated by trapped particles
论文作者
论文摘要
在存在捕获粒子的情况下，使用总的 - 皮塔夫斯基方程的数值模拟研究了量子涡流丝之间的重新连接。颗粒以经典的自由度描述，并被模型为耗尽超氟的高度排斥电位。首先，研究了一个涡旋偶极子，其中一个粒子被困在其中一个涡流中。结果表明，重新连接发生在粒子的位置，这是由于其引起的对称性破裂的结果。重新连接点之间的分离速率与量子涡流重新连接的已知动力学兼容，并且与粒子质量和大小无关。重新连接后，由于与涡旋丝的横向动量交换，粒子被恒定速度推开，其轨迹被偏转。表征了粒子，涡流和密度脉冲之间的动量交换。最后，研究了两个链接的环的重新连接，每个环都研究了几个最初随机分布的粒子。观察到，一般而言，重新连接发生在被困颗粒的位置。结果表明，重新连接动力学不受光颗粒的影响。
Reconnections between quantum vortex filaments in presence of trapped particles are investigated using numerical simulations of the Gross--Pitaevskii equation. Particles are described with classical degrees of freedom and modeled as highly repulsive potentials which deplete the superfluid. First, the case of a vortex dipole with a single particle trapped inside one of the vortices is studied. It is shown that the reconnection takes place at the position of the particle as a consequence of the symmetry breaking induced by it. The separation rate between the reconnecting points is compatible with the known dynamics of quantum vortex reconnections and it is independent of the particle mass and size. After the reconnection, the particle is pushed away with a constant velocity and its trajectory is deflected because of the transverse momentum exchange with the vortex filaments. The momentum exchanges between the particle, the vortex, and a density pulse are characterized. Finally, the reconnection of two linked rings, each of them with several initially randomly distributed particles is studied. It is observed that generically, reconnections take place at the location of trapped particles. It is shown that reconnection dynamics is unaffected for light particles.
