T. Shibauchi, L. Krusin-Elbaum, Y. Kasahara, Y. Shimono, Y. Matsuda, R. D. McDonald, C. H. Mielke, S. Yonezawa, Z. Hiroi, M. Arai, T. Kita, G. Blatter, M. Sigrist
YAMADA CONFERENCE LX ON RESEARCH IN HIGH MAGNETIC FIELDS 51 295 - + 2006年
[査読有り][通常論文] We determine the temperature dependence of the upper critical field H-c2 in KOs2O6 from resistivity and magnetic measurements in high magnetic fields up to 50 T. By both techniques we find linear temperature dependence all the way below T-c and uncommonly high H-c2 (T -> 0 K) similar to 33 T. We show that this unusual H-c2 can be understood as a consequence of paramagnetic limit Hp remarkably enhanced by the broken spatial inversion symmetry proposed recently, ensuring that the pair-breaking here is executed by orbital degrees, associated with the smaller closed Fermi surfaces.