Oscillatory motion: quantum whistling in superfluid helium-4.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 15674281.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
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.