论文标题
在扩展的北极星量子流体中的涡旋晶格的动力学
Dynamics of a vortex lattice in an expanding polariton quantum fluid
论文作者
论文摘要
如果量子流体用足够的角动量驱动，则在平衡状态下，系统的基态由定量涡旋的晶格给出，其密度是通过循环量化的。我们报告了Feynman-Onsager关系在非平衡极性流体中的首次实验研究，可以自由膨胀和旋转。最初在量子流体中刻有涡旋晶格后，我们跟踪皮秒时间尺度上的涡流核心位置。由于排斥的极性相互作用，我们观察到晶格的加速拉伸和涡流线性轨迹的外向弯曲。由于流体信封的密度梯度作用在涡旋晶格上的密度梯度，因此可以通过横向速度分量来检测与Feynman-Onsager规则的小偏差。
If a quantum fluid is driven with enough angular momentum, at equilibrium the ground state of the system is given by a lattice of quantised vortices whose density is prescribed by the quantization of circulation. We report on the first experimental study of the Feynman-Onsager relation in a non-equilibrium polariton fluid, free to expand and rotate. Upon initially imprinting a lattice of vortices in the quantum fluid, we track the vortex core positions on picosecond time scales. We observe an accelerated stretching of the lattice and an outward bending of the linear trajectories of the vortices, due to the repulsive polariton interactions. Access to the full density and phase fields allows us to detect a small deviation from the Feynman-Onsager rule in terms of a transverse velocity component, due to the density gradient of the fluid envelope acting on the vortex lattice.
