Low Temperature Physics: 34, 288 (2008); https://doi.org/10.1063/1.2908894 (5 pages)
Физика Низких Температур: Том 34, Выпуск 4-5 (Апрель 2008), c. 367-372    ( к оглавлению , назад )

Observation of acoustic turbulence in a system of nonlinear second sound waves in superfluid 4He

A.N. Ganshin1, V.B. Efimov1,2, G.V. Kolmakov1,2, P.V.E. McClintock1, and L.P. Mezhov-Deglin2

1Department of Physics, Lancaster University, Lancaster, LA1 4YB, UK

2Institute of Solid State Physics RAS, Chernogolovka, Moscow region, 142432, Russia
E-mail: mezhov@issp.ac.ru

Received October 30, 2007


We discuss the results of recent studies of acoustic turbulence in a system of nonlinear second sound waves in a high-quality resonator filled with superfluid 4He. It was found that, when the driving amplitude was sufficiently increased, a steady-state direct wave cascade is formed involving a flux of energy towards high frequencies. The wave amplitude distribution follows a power law over a wide range of frequencies. Development of a decay instability at high driving amplitudes results in the formation of subharmonics of the driving frequency, and to a backflow of energy towards the low-frequency spectral domain, in addition to the direct cascade.

PACS: 67.25.dg Transport, hydrodynamics, and superflow;
PACS: 67.25.dt Sound and excitations;
PACS: 47.27.Cn Transition to turbulence;
PACS: 05.20.Dd Kinetic theory.

Ключевые слова: superfluid helium, second sound, acoustic turbulence, Kolmogorov spectrum.