Open AccessINTERNAL FRICTION PEAK DUE TO MOVING FLUX IN Bi0.8 Pb0.2SrCaCuOy SUPERCONDUCTOR
Author(s) -
Jinxiu Zhang,
Zheng Wen-Guang,
Du Zhonglian,
Lin Guang-Ming,
Liang Kai-Feng,
Zhi-Cheng Lin
Publication year - 1990
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.39.84
Subject(s) - torsion pendulum clock , condensed matter physics , superconductivity , magnetic field , magnetization , internal friction , physics , materials science , torsion (gastropod) , field (mathematics) , composite material , quantum mechanics , medicine , surgery , mathematics , pure mathematics
The low-frequency internal friction in the magnetization process, where magnetic field increases linearly, is measured for (Bi0.8Pb0.2SrCaCuOy) in superconducting state by using a frequency variable inverted torsion pendulum system. Experimental conditions are as follows: measure temperature: 95 K, at which specimen is in resistance- free state; frequency: 0.5 Hz to 5 Hz. The characteristics of internal friction (IF) peak observed in curve of IF vs magnetic field strength H are as follows. 1. The peak height increases with an increasing of H (variance rate of magnetic field) but decreases as frequency increasing. 2. Magnetic field strength at which IF peak appears is 4-6 mT. 3. When H falis down to zero from a given value suddenly, IF peak disappears. 4. IF peak mentioned above disappears also when specimen turns to normal state.It is considered that, the eigen-IF of superconductor mentioned above during magnetization process stems from motion of quantum flux.