Liquid Helium

Vortex Photography in Liquid Helium

The study of quantized vortex lines has been advanced hy the technique of vortex photography. This paper prov~dex an overview of the information which has been acquired thus far from this method. Stationary cortex states are ohser\ed which are very similar to those predicted from theory. In addition types of dynamical phenomena are observed. such a\ collective oscillations and the acceleration ...

Quantum cavitation in liquid helium.

Using a functional-integral approach, we have determined the temperature below which cavitation in liquid helium is driven by thermally assisted quantum tunneling. For both helium isotopes, we have obtained the crossover temperature in the whole range of allowed negative pressures. Our results are compatible with recent experimental results on He. 64.60.Qb, 64.60.My, 67.80.Gb Typeset using REVT...

Cosmological experiments in liquid helium

Fast passage through a continuous phase transition is expected to result in the creation of topical defects via the Kibble mechanism. Recent experiments involving the expansion of a small volume of liquid He through the lambda (superfluid) transition, as a model of the GUT (grand unified theory) symmetrybreaking transition of the early universe, are discussed and set in context. Copious creatio...

Neutron reflection from the liquid helium surface

The Scattering of Light from Liquid Helium

A review is given of the scattering of light by superfluid helium. A brief discussion is given first of the theory of Brillouin and Rayleigh scattering from an ordinary simple pure liquid. It is shown how this discussion must be modified in the case of the superfluid phase of purc 4He, and experimental observations of Brillouin scattering from first sound in liquid helium are described. The dis...