EPL, 77 (2007) 66002
DOI: 10.1209/0295-5075/77/66002

Vortex density spectrum of quantum turbulence

P.-E. Roche¹, P. Diribarne¹, T. Didelot¹, O. Français^{2, 3}, L. Rousseau² and H. Willaime<sup>4

1</sup>  Institut NÉEL, CNRS & Université J. Fourier - 25 avenue des Martyrs, BP166, F-38042 Grenoble Cedex 9, France
²  Groupe ESIEE, Chambre de Commerce et d'Industrie de Paris - Cité Descartes, BP99, 2 boulevard Blaise Pascal, 93162 Noisy le Grand Cedex, France
³  Conservatoire National des Arts et Métiers, Laboratoire de Physique - 2 rue Conté, 75003 Paris, France
⁴  Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris - 10 rue Vauquelin, 75231 Paris Cedex 05, France

received 25 October 2006; accepted in final form 29 January 2007; published March 2007
published online 28 February 2007

Abstract
The fluctuations of the vortex density in a turbulent quantum fluid are deduced from local second-sound attenuation measurements. These measurements are performed with a micromachined open-cavity resonator inserted across a flow of turbulent He-II near 1.6 K. The frequency power spectrum of the measured vortex line density is compatible with a (-5/3) power law. The physical interpretation is discussed.

PACS
67.40.Vs - Vortices and turbulence.
47.37.+q - Hydrodynamic aspects of superfluidity; quantum fluids.
67.57.De - Quantum fluids and solids; liquid and solid helium: Superflow and hydro- dynamics.

© Europhysics Letters Association 2007