Low Temperature Physics: 40, 621 (2014); https://doi.org/10.1063/1.4887061
Физика Низких Температур: Том 40, Выпуск 7 (Июль 2014), c. 801-806    ( к оглавлению , назад )

Magnetic field penetration in MgB2 single crystals: pinning and Meissner holes

V. Chabanenko1, E. Kuchuk1, V.V. Yurchenko2, P. Mikheenko2, I. Abal’osheva3, R. Cortés-Maldonado4, F. Pérez-Rodríguez4, J. Karpinski5,6, N.D. Zhigadlo5

S. Katrych6, and R. Puźniak3

1A. Galkin Dоnetsk Institute for Physics and Engineering, NASU, Donetsk 83114, Ukraine
E-mail: vikchabanenko@gmail.com

2Department of Physics, University of Oslo, P.O. Box 1048, Blindern 0316, Oslo, Norway

3Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, Warsaw 02-668, Poland

4Instituto de Física, Benemérita Universidad Autónoma de Puebla, Puebla, México

5Laboratory for Solid State Physics, ETH Zurich, Zurich 8093, Switzerland

6Institute of Condensed Matter Physics, EPFL, Lausanne 1015, Switzerland

Received February 17, 2014


The evolution of flux distribution in MgB2 single crystals during their remagnetization was imaged with magneto-optical technique. Meissner holes, formed as the areas where the annihilation of vortices and antivortices takes place, were found at the boundary between oppositely magnetized parts of the crystal. Gradient of magnetic induction in the vicinity of Meissner holes was found to be enhanced. Finger-like structures of convex shape, formed during the penetration of magnetic flux inside the crystal, were observed and explained as an effect of inhomogeneous pinning and demagnetizing field redistribution in the sample.

PACS: 74.25.Ha Magnetic properties including vortex structures and related phenomena;
PACS: 78.20.Ls Magneto-optical effects;
PACS: 74.25.Wx Vortex pinning (includes mechanisms and flux creep).

Key words: magnetooptic of flux penetration, vortices, antivortices, Meissner holes, inhomogeneous pinning, single crystal MgB2.

Published online: May 21, 2014