Low Temperature Physics: 35, 627 (2009); https://doi.org/10.1063/1.3224718 (5 pages)
Fizika Nizkikh Temperatur: Volume 35, Number 8-9 (August 2009), p. 798-804    ( to contents , go back )

Development of macroturbulent instability in a YBCO single crystal

I.F. Voloshin, A.V. Kalinov, L.M. Fisher

ФГУП "Всероссийский электротехнический институт", ул. Красноказарменная, 12, г. Москва, 111250, Россия

V.A. Yampol’skii

A. Usikov Institute of Radiophysics and Electronics of the National Academy of Sciences of Ukraine 12 Acad. Proskura Str., Kharkov 61085, Ukraine
E-mail: yam@ire.kharkov.ua

A. Bobyl and T.H. Johansen

Department of Physics, University of Oslo, P.O. Box 1048, Blindern, 0316 Oslo, Norway
pos Анотація:

Received December 29, 2008

Abstract

The macroturbulence in a superconducting YBCO single crystal is studed experimentally. The macroturbulence arises with changing the sign of external magnetic field which results in the appearance of a magnetization reversal front dividing the spatial regions occupied by vortices with opposite orientations (vortices and antivortices). The measurements were carried out at temperature 40 K by using the magnetooptic-imaging technique. It is found that the time of macroturbulence development depends strongly on the value of external magnetic field H. As H is increased, the macroturbulent process accompanied by the vortex-antivortex annihilation, is intensified due to an increase of the flux creep.

PACS: 74.25.Ha Magnetic properties;
PACS: 74.25.Qt Vortex lattices, flux pinning,flux creep;
PACS: 74.25.Sv Critical currents.

Key words: macroturbulence, twin boundaries, anisotropic flux flow.

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