AI Article Synopsis
- The particle flux through a tiny hole from solid 4He into a vacuum shows periodic bursts, which vary with pressure and temperature.
- These bursts disappear at the melting point when temperatures exceed 1.76 K, indicating a change in behavior.
- The observed oscillations are linked to the collapse of solid 4He caused by excess vacancies created at the orifice, and below 1.76 K, significant changes in flow properties are noted due to these vacancies.
Article Abstract
The particle flux through a micron-sized orifice into vacuum from a source chamber filled with solid 4He exhibits a striking sequence of periodic bursts. The period increases (decreases) with pressure (temperature), vanishing at the melting point for temperatures above the upper lambda point at 1.76 K. The oscillations are attributed to a periodic collapse of the solid induced by the accumulation of excess vacancies injected at the orifice and the period provides information on vacancy diffusivity. Dramatic deviations from this behavior below 1.76 K suggest important modifications in the flow properties of solid 4He induced by the excess vacancies.
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| http://dx.doi.org/10.1103/PhysRevLett.95.095301 | DOI Listing |
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