半整数磁流量量子的温度依赖性
1IBM T. J. Watson Research Center, Post Office Box 218, Yorktown Heights, NY 10598, USA. Department of Applied Physics, Stanford University, Stanford, CA 94305, USA.
Science (New York, N.Y.)
|August 28, 1999
概括
在乙,,铜氧化物 (YBCO) 中,半整数磁流量量子效应从0.5K持续到90K,表明D波对接占主导地位. 这表明这种高温超导体的时间逆向对称性破裂最小.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 超导电性 超导电性 超导电性
背景情况:
- 高温铜酸超导体,如亚铁和铜氧化物 (YBa(2) Cu(3) O(7-delta),具有复杂的电子特性.
- 半整数磁流量量子效应是一种在某些超导系统中观察到的现象.
- 了解这些材料中的配对对称性和时间逆转对称性对于基本物理学和潜在应用至关重要.
研究的目的:
- 为了研究半整数磁流量量子效应在YBa(2) Cu(3) O(7-delta) 薄膜中的温度依赖性.
- 为了确定这种效应在广泛的温度范围内的持久性,从低温到临界温度.
- 推断主导配对对称性和超导体时间逆转对称性破坏的程度.
主要方法:
- 制造YBa(2)Cu(3)O(7-delta) 的薄膜三晶样本.
- 精确测量磁流量子效应作为温度的函数.
- 在超导过渡过程中对总流量行为的分析.
主要成果:
- 观察到半整数磁流量量子效应从0.5凯尔文持续到约90凯尔文的临界温度.
- 在整个温度范围内,没有检测到总流量的变化.
- 观察到的现象在不同温度下保持一致,低于临界温度.
结论:
- 效应的持久性强烈地暗示d波对称配对是YBa(2) Cu(3) O(7-delta) 中的主导配对机制.
- 结果表明时间逆向对称性在测量温度范围内存在最小的,如果有的话.
- 这为这种高临界温度酸盐的基本超导特性提供了重要的洞察力.
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