论文标题
表面主导的有限尺寸效应纳米夹层的超流体氦
Surface-dominated finite size effects in nanoconfined superfluid helium
论文作者
论文摘要
超氟$^4 $ He（He-II）是一个经过广泛研究的模型系统，用于探索强限制的几何形状中的有限尺寸效果。在这里，我们研究使用纳米荧光Helmholtz谐振器，在高压高度高25和50 nm的MM级通道中进行研究。我们发现，从过渡温度降低到0.6 K的限制几何形状可以测量超氟密度。
Superfluid $^4$He (He-II) is a widely studied model system for exploring finite-size effects in strongly confined geometries. Here, we study He-II confined in mm-scale channels of 25 and 50 nm height at high pressures using a nanofluidic Helmholtz resonator. We find that the superfluid density is measurably suppressed in the confined geometry from the transition temperature down to 0.6 K. Importantly, this suppression can be accounted for by roton-like thermal excitation with an energy gap of 5 K. We show that the surface-bound excitations lead to the previously unexplained lack of finite-size scaling of suppression of the superfluid density.
