Ultrasound anomaly at Tc in YBa2Cu3Oy |
| |
Institution: | 1. Los Alamos National Laboratory P.O. Box 1663, Los Alamos, NM 87545, USA;2. Department of Physics and Solid State Science Center University of California, Los Angeles, CA. 90024, USA;1. Renewable Energy Design Laboratory, Department of Mechanical Engineering, University of Hawaii at Manoa, 2540 Dole St., Holmes Hall 347, Honolulu, HI 96822, USA;2. Hawaii Natural Energy Institute, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 1680 East-West Road, POST 110, Honolulu, HI 96822, USA;1. GREiA Research Group, INSPIRES Research Centre, University of Lleida, Pere de Cabrera s/n, 25001 Lleida, Spain;2. Department of Mechanical, Energy and Management Engineering, University of Calabria, P. Bucci 46/C, 87036 Rende, Italy;1. EA4203 Bio-nano laboratory, faculty of dentistry of Montpellier, 545, avenue du Pr JL Viala, 34193 Montpellier cedex 5, France;2. Faculty of dentistry of Paris Descartes, 92120 Montrouge, France;3. Inserm, UMR1153, obstetrical, perinatal, and pediatric epidemiology (EPOPE) Team, Epidemiology and Biostatistics, Sorbonne Paris Cité Research Center, 75004 Paris, France;4. EA2415 clinical research university institute (IURC), faculty of dentistry of Montpellier, 545, avenue du Pr JL Viala, 34193 Montpellier cedex 5, France;5. Inserm UMR 1027, faculty of dentistry of Toulouse, Toulouse university, 3, chemin des Maraîchers, 31062 Toulouse cedex 09, France;1. State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China;2. University of Chinese Academy of Sciences, Beijing 100049, China |
| |
Abstract: | We measured the fundamental longitudinal acoustic resonant frequency fr of polycrystalline samples of YBa2Cu3Oy. The frequency increases with decreasing temperature and displays a sharp rise as we cool below Tc. The fractional change in frequency at Tc, Δfr/fr, is 4.5 × 10-3 and is opposite in sign to that expected at the usual second-order super-conducting transition. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|