MEASUREMENTS OF VORTEX-TRANSPORT ENTROPY IN EPITAXIAL ND1.85CE0.15CUO4-DELTA FILMS - EVIDENCE FOR QUASI-PARTICLE BOUND-STATE QUANTIZATION IN THE VORTEX CORE

被引:10
作者
JIANG, XG [1 ]
JIANG, W [1 ]
MAO, SN [1 ]
GREENE, RL [1 ]
VENKATESAN, T [1 ]
LOBB, CJ [1 ]
机构
[1] UNIV MARYLAND,CTR SUPERCONDUCT RES,DEPT PHYS,COLLEGE PK,MD 20742
来源
PHYSICA C | 1995年 / 254卷 / 1-2期
关键词
D O I
10.1016/0921-4534(95)00531-5
中图分类号
O59 [应用物理学];
学科分类号
摘要
We report measurements of the vortex-transport entropy in the high-temperature superconductor Nd1.85Ce0.15CuO4-delta. The vortex transport entropy, determined from flux-flow Nernst effect and resistivity measurements, is about 100 times smaller than Maki's theoretical prediction. Using a simple microscopic model, we show that the entropy decrease is a result of the large energy level spacing between quasiparticle bound states in the vortex core, providing strong evidence for the discreteness of these states.
引用
收藏
页码:175 / 180
页数:6
相关论文
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