Partial suppression of superconductivity by fast cooling has been observed in the organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br by two means: a marked sample size effect on the magnetic susceptibility and direct imaging of insulating regions by scanning microregion infrared reflectance spectroscopy. Macroscopic insulating regions are proposed in the vicinity of the crystalline surface after fast cooling, with diameters of 50-100μm and depths of a few μm. The very large in-plane penetration depth reported to date (∼24-100μm) can be explained by the existence of the insulating regions.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2005 Dec 1|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics