空气稳定的半导体中的轴依赖导电极性,PdSe2
Ryan A Nelson1, Ziling Deng2, Andrew M Ochs1
1Dept of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Ave., Columbus, OH 43210, USA. goldberger.4@osu.edu.
Materials horizons
|July 5, 2023
概括
这项研究表明,二化 (PdSe2) 是一种稳定的半导体,具有轴依赖导电极性 (ADCP). 这种独特的电子特性使得电荷载体可以根据方向不同地移动,从而开辟了新的技术可能性.
科学领域:
- 固态物理 固态物理
- 材料科学 材料科学 材料科学
- 半导体物理 半导体物理
背景情况:
- 轴依赖导电极性 (ADCP) 是一种罕见的电子现象,其中电荷载体类型 (p型或n型) 随着晶体方向而变化.
- 大多数已知的ADCP材料都是金属,很少有半导体表现出这种效应,限制了其实际应用.
研究的目的:
- 确定二化 (PdSe2) 是一种表现出ADCP的稳定半导体.
- 为了研究ADCP在化PdSe2晶体中的运输特性和潜在机制.
主要方法:
- 化 (p型) 和化 (n型) PdSe2晶体的生长和特征.
- 测量各种温度范围和兴奋剂水平的传输特性,包括导电性和热功率.
- 密度函数理论 (DFT) 计算以阐明ADCP的起源.
主要成果:
- 稳定的半导体PdSe2用电子合样本展示了ADCP,显示了p型传导横平面和n型传导在100-200K以上的平面内.
- P-doped PdSe2 呈现出温度依赖的热力,在平面内热力变为负值以上~360 K.
- DFT计算证实了价值带和导电带的有效质量异质性驱动了PdSe2.2中的ADCP.
结论:
- PdSe2是实现ADCP的有希望的稳定半导体材料.
- 在PdSe2中观察到的ADCP源于固有的带结构特性,使方向电荷传输成为可能.
- 这一发现为利用定向电荷迁移的新型电子设备和技术开辟了道路.
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