超导和电荷密度波形转换在Th2Cu4作为5
Shaohua Liu1, Qingchen Duan1, Baizhuo Li1,2
1School of Physics and Optoelectronic Engineering, Shandong University of Technology, Zibo 255000, P. R. China.
Journal of the American Chemical Society
|March 18, 2024
概括
我们发现了一种新材料,-铜-化物 (Th2Cu4As5),
科学领域:
- 凝聚物质物理学
- 材料科学
- 固态化学
背景情况:
- 含有,铜和的三元化合物因其独特的电子和结构性质而引起兴趣.
- 了解不同结构图案与超导和电荷密度波等新兴现象之间的相互作用至关重要.
研究的目的:
- 合成和描述一种新的三元化合物Th2Cu4As5.
- 研究其晶体结构和物理特性,包括超导性和潜在电荷密度波 (CDW) 过渡.
主要方法:
- 单晶X射线衍射用于结构确定.
- 测量电阻,磁性易感性和比热.
- 霍尔系数测量探测电荷载体的行为.
- 支持实验发现的带结构计算.
主要成果:
- Th2Cu4As5结晶成一个四面体结构 (空间组P4/mm) 格子参数a = 4.0639(3) Å和c = 24.8221(17) Å.
- 该结构由交替的Th2As2化物层和Cu4As3抗化物板组成.
- 在过渡温度 (T_c) 为4. 2K时观察到散装超导性.
- 在48K的物理特性中的异常,包括霍尔系数的变化,表明电荷密度波形 (CDW) 阶段过渡.
- 带计算表明超导性源于Cu4As3板块,CDW从Th2As2层中的As平面过渡.
结论:
- Th2Cu4As5是一种新型超导体,具有明显的CDW相变.
- 不同的结构单元 (Cu4As3板和Th2As2层) 可能是观察到的超导和CDW现象的原因.
- 这一发现为基于三元的金属间化合物的复杂相位行为提供了新的见解.
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