Publication Date
7-31-2018
Department
Ames Laboratory; Physics and Astronomy
Campus Units
Physics and Astronomy, Ames Laboratory
OSTI ID+
1464489
Report Number
IS-J 9647
DOI
10.1038/s41598-018-29750-7
Journal Title
Scientific Reports
Volume Number
8
First Page
11480
Abstract
Enhanced microwave absorption, larger than that in the normal state, is observed in fine grains of type-II superconductors (MgB2 and K3C60) for magnetic fields as small as a few % of the upper critical field. The effect is predicted by the theory of vortex motion in type-II superconductors, however its direct observation has been elusive due to skin-depth limitations; conventional microwave absorption studies employ larger samples where the microwave magnetic field exclusion significantly lowers the absorption. We show that the enhancement is observable in grains smaller than the penetration depth. A quantitative analysis on K3C60 in the framework of the Coffey–Clem (CC) theory explains well the temperature dependence of the microwave absorption and also allows to determine the vortex pinning force constant.
Language
en
Publisher
Iowa State University Digital Repository, Ames IA (United States)
