ePrints

Visualization of quantum turbulence in superfluid ³He-B: Combined numerical and experimental study of Andreev reflection

Lookup NU author(s): Dr Andrew BaggaleyORCiD, Emeritus Professor Yuri Sergeev, Professor Carlo Barenghi, Dr Nugzar Suramlishvili

Downloads

• Published version [.pdf]

Licence

This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).

Abstract

We present a combined numerical and experimental study of Andreev scattering from quantum turbulence in superfluid ³He-B at ultralow temperatures. We simulate the evolution of moderately dense, three-dimensional, quasiclassical vortex tangles and the Andreev reflection of thermal quasiparticle excitations by these tangles. This numerical simulation enables us to generate the two-dimensional map of local Andreev reflections for excitations incident on one of the faces of a cubic computational domain, and to calculate the total coefficient of Andreev reflection as a function of the vortex line density. Our numerical simulation is then compared with the experimental measurements probing quantum turbulence generated by a vibrating grid. We also address the question of whether the quasiclassical and ultraquantum regimes of quantum turbulence can be distinguished by their respective total Andreev reflectivities. We discuss the screening mechanisms which may strongly affect the total Andreev reflectivity of dense vortex tangles. Finally, we present combined numerical-experimental results for fluctuations of the Andreev reflection from a quasiclassical turbulent tangle and demonstrate that the spectral properties of the Andreev reflection reveal the nature and properties of quantum turbulence.

Publication metadata

Author(s): Tsepelin V, Baggaley AW, Sergeev YA, Barenghi CF, Fisher SN, Pickett GR, Jackson MJ, Suramlishvili N

Publication type: Article

Publication status: Published

Journal: Physical Review B

Year: 2017

Volume: 96

Issue: 5

Online publication date: 14/08/2017

Acceptance date: 18/07/2017

Date deposited: 19/07/2017

ISSN (print): 2469-9950

ISSN (electronic): 2469-9969

Publisher: American Physical Society

URL: https://doi.org/10.1103/PhysRevB.96.054510

DOI: 10.1103/PhysRevB.96.054510

Data Access Statement: http://dx.doi.org/10.17635/lancaster/researchdata/162

Altmetrics

Funding

Share