Adhikari S K, Salasnich L
Instituto de Física Teórica, UNESP - Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo, Brazil.
Dipartimento di Fisica e Astronomia "Galileo Galilei", Università di Padova, Via Marzolo 8, 35131, Padova, Italy.
Sci Rep. 2018 Jun 11;8(1):8825. doi: 10.1038/s41598-018-27146-1.
The formation of a regular lattice of quantized vortices in a fluid under rotation is a smoking-gun signature of its superfluid nature. Here we study the vortex lattice in a dilute superfluid gas of bosonic atoms at zero temperature along the crossover from the weak-coupling regime, where the inter-atomic scattering length is very small compared to the average distance between atoms, to the unitarity regime, where the inter-atomic scattering length diverges. This study is based on high-performance numerical simulations of the time-dependent nonlinear Schrödinger equation for the superfluid order parameter in three spatial dimensions, using a realistic analytical expression for the bulk equation of state of the system along the crossover from weak-coupling to unitarity. This equation of state has the correct weak-coupling and unitarity limits and faithfully reproduces the results of an accurate multi-orbital microscopic calculation. Our numerical predictions of the number of vortices and root-mean-square sizes are important benchmarks for future experiments.
在旋转流体中形成规则的量子化涡旋晶格是其超流性质的确凿标志。在此，我们研究零温下玻色原子稀薄超流气体中的涡旋晶格，该研究涵盖从弱耦合 regime（其中原子间散射长度相较于原子平均间距非常小）到幺正 regime（其中原子间散射长度发散）的交叉区域。这项研究基于对三维空间中描述超流序参量的含时非线性薛定谔方程进行的高性能数值模拟，使用了一个沿从弱耦合到幺正的交叉区域的系统体状态方程的现实解析表达式。该状态方程具有正确的弱耦合和幺正极限，并忠实地再现了精确多轨道微观计算的结果。我们对涡旋数量和均方根尺寸的数值预测是未来实验的重要基准。
