在中直接观察压力诱导的金属到半导体的过渡
Takahiro Matsuoka1, Katsuya Shimizu
1KYOKUGEN, Center for Quantum Science and Technology under Extreme Conditions, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan. matsuoka@djebel.mp.es.osaka-u.ac.jp
Nature
|March 13, 2009
概括
是一种简单的金属,在高压下意外转化为半导体. 电阻测量揭示了这种压力诱导的金属到半导体的过渡,挑战了以前的模型.
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
- 高压物理 高压物理
背景情况:
- 是最轻的金属,传统上以几乎自由电子的电子结构为模型.
- 在压缩下,理论计算表明可能过渡到半金属或半导体状态.
- 实验证据表明,密集的采用了低对称性结构,并且在压力下增加了电阻.
研究的目的:
- 在高静压下实验性地研究的电子传输特性.
- 为了提供直接的电阻测量作为压力的函数.
- 为了证实或驳斥中压力诱导的电子相变的理论预测.
主要方法:
- 的电阻测量是使用钻石天细胞进行的.
- 测量结果达到105 GPa的静态压力.
- 在各种压力下监测电阻的温度依赖性.
主要成果:
- 随着压力增加,电阻的显著增加被观察到.
- 在80 GPa左右,电阻的温度依赖性发生了明显的变化.
- 这些发现为金属到半导体的过渡提供了明确的实验证据.
结论:
- 高压诱导的金属到半导体的过渡.
- 在压缩下的电子行为偏离了简单的几乎自由电子模型.
- 这项研究提供了极端条件下的"简单"元素中复杂电子行为的直接实验验证.
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