Synthesis and Precise Analysis of Bi2Sr2Can-1CunOy Superconducting Whiskers

Abstract

We synthesized Ca-rich Bi-based superconducting whiskers by an Al2O3-seeded glassy quenched platelet method. The grown whiskers were precisely characterized by synchrotron radiation X-ray photoemission spectroscopy and high-resolution transmission electron microscopy. The Ca-rich Bi-based superconducting whiskers show a high critical current density of 2×105A/cm2 at 40K in self-field. We found that excess Ca2+ ions substitute for the Sr2+ sites and cause nano crystalline domains with shorter-period modulation embedded in the base crystalline. The embedded nano crystalline domains can result in structural distorted defects which work as strong pinning center.