National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL, 32310, USA.
Mechanical Engineering Department, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, 32310, USA.
Nat Commun. 2023 May 23;14(1):2941. doi: 10.1038/s41467-023-38787-w.
The motion of quantized vortices is responsible for many intriguing phenomena in diverse quantum-fluid systems. Having a theoretical model to reliably predict the vortex motion therefore promises a broad significance. But a grand challenge in developing such a model is to evaluate the dissipative force caused by thermal quasiparticles in the quantum fluids scattering off the vortex cores. Various models have been proposed, but it remains unclear which model describes reality due to the lack of comparative experimental data. Here we report a visualization study of quantized vortex rings propagating in superfluid helium. By examining how the vortex rings spontaneously decay, we provide decisive data to identify the model that best reproduces observations. This study helps to eliminate ambiguities about the dissipative force acting on vortices, which could have implications for research in various quantum-fluid systems that also involve similar forces, such as superfluid neutron stars and gravity-mapped holographic superfluids.
量子涡旋的运动是许多不同量子流体系统中有趣现象的原因。因此，拥有一个可靠地预测涡旋运动的理论模型具有广泛的意义。但是，开发这样一个模型的一个巨大挑战是评估在量子流体中散射的热准粒子对涡核的耗散力。已经提出了各种模型，但由于缺乏比较性的实验数据，因此仍然不清楚哪种模型描述了现实。在这里，我们报告了在超流氦中传播的量子涡环的可视化研究。通过检查涡环如何自发衰减，我们提供了决定性的数据来确定最能再现观测结果的模型。这项研究有助于消除作用在涡旋上的耗散力的模糊性，这对于涉及类似力的各种量子流体系统的研究具有重要意义，例如超流中子星和引力映射全息超流体。
