12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Creation of quantized vortices at the lambda tr...
View graph of relations

« Back

Creation of quantized vortices at the lambda transition in liquid Helium-4.

Research output: Contribution to journalJournal article

Published

Journal publication date12/1993
JournalJournal of Low Temperature Physics
Journal number5/6
Volume93
Number of pages9
Pages1059-1067
Original languageEnglish

Abstract

A fast (ca. 3 ms) adiabatic expansion of a volume of liquid He-4 through the lambda transition is being used to study the nature of the transition and to model the cosmological false vacuum to true vacuum phase transition of the early universe. Preliminary results are reported showing that, in accordance with theoretical predictions by W H Zurek (Nature 317, 505; 1985), there is copious production of quantized vortex lines, which represent the superfluid analogue of cosmic strings. The line density after the expansion appears to decay in two distinct stages, with a fast decay being followed by a much slower one, in agreement with earlier work on the decay of quantum turbulence created in thermal counterflow. Extrapolation of the initial fast decay suggests an initial line density, immediately following the expansion, of ca. 10 to power 7 per square cm. Smaller, but still substantial, vortex densities are also found to occur when the system is expanded from below the lambda transition, and the physical implications are discussed.

Bibliographic note

Proceedings of the Conference on the Role of the Condensate and Vorticity in Dense Bose Systems, 1-3 August 1993, in Minneapolis.