Fisher, Shaun and Jackson, Martin and Sergeev, Y. A. and Tsepelin, Viktor (2014) Andreev reflection, a tool to investigate vortex dynamics and quantum turbulence in 3He-B. Proceedings of the National Academy of Sciences of the United States of America, 111 (Supple). pp. 4659-4666. ISSN 0027-8424
Full text not available from this repository.Abstract
Andreev reflection of quasiparticle excitations provides a sensitive and passive probe of flow in superfluid 3He-B. It is particularly useful for studying complex flows generated by vortex rings and vortex tangles (quantum turbulence). We describe the reflection process and discuss the results of numerical simulations of Andreev reflection from vortex rings and from quantum turbulence. We present measurements of vortices generated by a vibrating grid resonator at very low temperatures. The Andreev reflection is measured using an array of vibrating wire sensors. At low grid velocities, ballistic vortex rings are produced. At higher grid velocities, the rings collide and reconnect to produce quantum turbulence. We discuss spatial correlations of the fluctuating vortex signals measured by the different sensor wires. These reveal detailed information about the formation of quantum turbulence and about the underlying vortex dynamics.