Direct observation of vortex lattice melting in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8+/spl delta// single crystals

Author

Bending, S.J. ; Oral, A. ; Clem, J.R. ; Kaya, I.I. ; Ooi, S. ; Tamegai, T. ; Henini, M.

Author_Institution

Dept. of Phys., Bath Univ., UK

Volume

9

Issue

2

fYear

1999

fDate

6/1/1999 12:00:00 AM

Firstpage

1820

Lastpage

1823

Abstract

Scanning Hall probe microscopy has been used to investigate the melting of the vortex solid in Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8+/spl delta// single crystals. After waiting several minutes for fluctuations to die away, a flux solid with good six-fold order is observed below the melting line. Incommensurability effects lead to pronounced rotations of the solid as the field is varied. The peak-to-valley corrugation of the vortex lattice drops abruptly and discontinuously to zero at the melting line, consistent with a first order transition. Fits of a pancake vortex model to the data yield a Lindemann parameter C/sub L//spl sim/0.19 in fair agreement with other estimates. There is also a clear indication of softening of the solid at very low fields, though we find no direct evidence for re-entrant melting.

Keywords

bismuth compounds; calcium compounds; flux-line lattice; high-temperature superconductors; scanning probe microscopy; strontium compounds; Bi/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/; Lindemann parameter; first order transition; incommensurability; pancake vortex model; scanning Hall probe microscopy; single crystals; six-fold order; vortex lattice melting; Bismuth; Crystals; Fluctuations; Hall effect devices; Lattices; Microscopy; Softening; Solids; Strontium; Yield estimation;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.784810

Filename

784810