Magnetic-field enhancement of 63Cu and 17O relaxation rates in the mixed state of YBa2Cu4O8 observation of fermi-liquid state in the vortex cores

✍ Scribed by Guo-qing Zheng; Yoshio Kitaoka; Kunisuke Asayama; Yasuharu Kodama

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 548 KB
• Volume: 227
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(94)90370-0

✦ Synopsis

The 63Cu and "0 nuclear spin-lattice relaxation rates in YBa$&Os have been measured in the temperature and magnetic field ranges of 1.4-270 K and 4.0-11 T, respectively. In the mixed state, 1 /T, for both 63Cu and "0 are enhanced by the magnetic field. Most strikingly, in a high field of 11 T, 63 ( 1 / T, ) and " ( 1 / T, ) decrease in proportion to the temperature, T, below T= 15 K and T= 10 K, respectively. The magnetic-field dependence of 1 /T, is shown to be dominated by spin diffusion to the vortex cores, implying that the electronic state in the cores is characterized by the T,T=const. law. This result indicates that the electronic state in the vortex cores is described in terms of the Fermi-liquid picture, in sharp contrast to the unusual properties above T,.