Horst Meyer and Quantum Evaporation

Abstract

With their 1963 article in Cryogenics Horst Meyer and his collaborators triggered intense research activity on the evaporation of superfluid helium. Discussing this subject with him in 1975 was enlightening. Fifty years later, the analogy between the photoelectric effect and the evaporation of superfluid helium in the low temperature limit is not yet clear, although remarkable progress has been made in its observation and its understanding. This special issue of the Journal of Low Temperature Physics is an opportunity to recall the history of quantum evaporation, and to express my gratitude to Horst Meyer. It describes quickly most of the experimental and theoretical works which have been published on quantum evaporation during the last 50 years, but it is not a comprehensive review of this fascinating subject.

Dark Matter Detection Using Helium Evaporation and Field Ionization

“…The phonons and the rotons that have an energy above about 0.7 meV propagate through the liquid without scattering or decay [23]. When one of these excitations reaches the free surface of the helium, a process called quantum evaporation can eject a helium atom [24][25][26]. The wafer/calorimeter was positioned above the liquid surface in a way that maintained the wafer free of a superfluid helium film [27].…”

Use of Superfluid Helium to Observe Directionality of Galactic Dark Matter

“…Nothing is soluble in liquid 4 He except for the rarer isotope 3 He. And two, it is possible to extract from the bulk liquid, at very low temperature, the thermal energy deposited by a scattering event using the process of quantum evaporation [2,3]. There have subsequently been many papers discussing such topics as its use for detection of dark matter [4,5], experimental studies of energy deposition in liquid helium [6][7][8][9][10][11][12][13], different possible designs of detectors [14,15], calculations of expected discrimination between nuclear and electron recoils [16,17].…”