J. Phys. IV France 12 (2002) Pr9-177
DOI: 10.1051/jp4:20020388

Increase of the charge density wave phase coherence in the sliding and the mode-locked state

R. Danneau^{1, 2}, A. Ayari¹, D. Rideau^{1, 2}, H. Requardt³, J.E. Lorenzo⁴, L. Ortega⁴, P. Monceau^{1, 5}, R. Currat² and G. Grübel<sup>3

1</sup>  Centre de Recherches sur les Tres Basses Temperatures, CNRS, BP. 166,38042 Grenoble, France
²  Institut Laue-Langevin, BP. 156, 38042 Grenoble, France
³  European Synchrotron Radiation Facility, BP. 220, 38043 Grenoble, France
⁴  Laboratoire de Cristallographie, CNRS, BP. 166, 38042 Grenoble, France
⁵  Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif-sur-Yvette cedex, France

Abstract
Using high-resolution x-ray techniques coupled to in situ electrical measurements, we have measured the spatial coherence of the charge density waves (CDW) in the sliding state without and with a rf field. In the first case, at T = 100 K , we find that the CDW becomes more ordered in the direction of the motion, while the transverse correlation is reduced. With the application of a rf field in the mode locked state, we find that the longitudinal correlation length is even larger.

© EDP Sciences 2002