| Title | Vortex Redistribution below the First-Order Transition Temperature in the beta-Pyrochlore Superconductor KOs2O6. | | Author(s) | Shibauchi T, Konczykowski M, van der Beek CJ, Okazaki R, Matsuda Y, Yamaura J, Nagao Y, Hiroi Z | | Institution | Department of Physics, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and Laboratoire des Solides Irradiés, Ecole Polytechnique, 91128 Palaiseau cedex, France. | | Source | Phys Rev Lett 2007 Dec 21; 99(25):257001. | | Abstract | A miniature Hall-sensor array was used to detect magnetic induction locally in the vortex states of the beta-pyrochlore superconductor KOs2O6. Below the first-order transition at T_{p} approximately 8 K, which is associated with a change in the rattling motion of K ions, the lower critical field and the remanent magnetization both show a distinct decrease, suggesting that the electron-phonon coupling is weakened below the transition. At high magnetic fields, the local induction shows an unexpectedly large jump at T_{p} whose sign changes with position inside the sample. Our results demonstrate a novel redistribution of vortices whose energy is reduced abruptly below the first-order transition at T_{p}. | | Language | eng | | Pub Type(s) | Journal Article
| | PubMed ID | 18233548 |
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