近日，加拿大不列颠哥伦比亚大学P. C. E. Stamp团队研究了二维4He超流膜中涡旋的真空隧道。这一研究成果于2025年9月2日发表在《美国科学院院刊》杂志上。

在低温下，研究组预计真空隧道过程发生在超流体4He薄膜中。他们区分了外在过程和内在过程。外在过程是指单个涡旋在系统边界外隧穿成核，内在过程是指涡旋/反涡旋对在远离边界的地方成核。在隧道计算中，考虑旋涡有效质量的变化是至关重要的。

本征过程是量子场论中Schwinger机制的超流体模拟；它们在T = 0时表现为量子相变，由外部超电流驱动。研究组计算了这些过程的隧穿率，并描述了一种测试预测的方法，这些预测均基于一个特定的“漩涡计数”实验。

附：英文原文

Title: Vacuum tunneling of vortices in two-dimensional 4He superfluid films

Author: Desrochers, M. J., Marchand, D. J. J., Stamp, P. C. E.

Issue&Volume: 2025-9-2

Abstract: At low temperature T we expect vacuum tunneling processes to occur in superfluid 4He films. We distinguish between extrinsic processes, in which single vortices nucleate by tunneling off boundaries in the system, and intrinsic processes, in which vortex/anti-vortex pairs nucleate far from boundaries. It is crucial to incorporate the varying effective mass of the vortex in tunneling calculations. The intrinsic processes are the superfluid analogue of the Schwinger mechanism in quantum field theory; here they appear as a quantum phase transition at T = 0, driven by an external supercurrent. We calculate the tunneling rate for these processes, and describe a means of testing the predictions using a specific “vortex counting” experiment.

DOI: 10.1073/pnas.2421273122

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2421273122