Hoskinson E, Packard R E, Haard Thomas M
Physics Department, University of California, Berkeley, California 94720, USA.
Nature. 2005 Jan 27;433(7024):376. doi: 10.1038/433376a.
Fundamental considerations predict that macroscopic quantum systems such as superfluids and the electrons in superconductors will undergo oscillatory motion when forced through a small constriction. Here we induce these oscillations in superfluid helium-4 (4He) by pushing it through an array of nanometre-sized apertures. The oscillations, which are detected as an audible whistling sound, obey the so-called Josephson frequency relation and occur coherently among all the apertures. The discovery of this property in 4He at the relatively high temperature of 2 K (2,000 times higher than the temperature at which a related but different phenomenon occurs in 3He) may pave the way for a new class of practical rotation sensors of unprecedented precision.
基本原理预测，诸如超流体和超导体中的电子等宏观量子系统在被迫通过一个小的缩颈时会发生振荡运动。在这里，我们通过将超流氦-4（4He）推过一系列纳米尺寸的孔来诱导这些振荡。这些振荡被检测为一种可听见的啸声，遵循所谓的约瑟夫森频率关系，并且在所有孔之间相干地发生。在2K这个相对较高的温度下（比3He中发生相关但不同现象的温度高2000倍）在4He中发现这一特性，可能为一类前所未有的高精度实用旋转传感器开辟道路。
