COLLABORATION IN BASIC SCIENCE AND ENGINEERING (COBASE)

In just four short months of work at Iowa State University with his host, Vladimir Kogan, Lev Vinnikov of the Institute of Solid State Physics managed to achieve something never before reported in the field of superconductor physics. Kogan had been invited to Ames to set up and operate a special piece of equipment used for "decorating" vortices in type-II semiconductors. When he arrived August 2000, he brought with him a special cryostat he had built back in Russia, and using this device he and his colleagues hoped to broaden the common field region of the decoration to the kilogauss range. According to Kogan, Vinnikov's expertise proved invaluable, as building such a device and bringing it to operational condition would have taken years of effort on the part of the ISU researchers.

While in Ames, Vinnikov succeeded in pushing the decoration technique to fields as high as 2kG, an achievement with no precedent. A paper describing these results has been submitted for publication by Physical Review B, and a second paper is in preparation. In addition, Kogan and other ISU co-authors will report on their findings at the March 2001 Meeting of the American Physical Society in Seattle.

As for the future, Kogan states that he intends to continue working with Vinnikov to further extend the limits of the decoration technique, which should open new prospects for the study of superconductors in the vortex state. Future research efforts will include additional materials, in particular those where superconductivity coexists with either antiferromagnetic or possibly ferromagnetic order. The partners are currently working on a proposal to NSF to support their continued collaboration.