SYNTHESIS AND STM INVESTIGATION OF RARE-EARTH SUPERCONDUCTING BOROCARBIDES

Rare-earth borocarbide superconductors (RE-Ni2B2C) have recently attra cted the attention of researchers because of their intriguing supercon ducting and magnetic properties, in the present paper we report on the in situ synthesis of high-quality thin films of these materials (RE=Y , Er) using planar magnetron sputtering. Low-temperature STM tunnellin g investigations were performed on films and single crystals. The STM results, together with d.c. transport measurements, give strong eviden ce of the weak-coupling BCS nature of these compounds. A discussion of the magnetic vortex structure and of the interplay of superconductivi ty and magnetism is also included.