穿孔合的La3Ni2O7薄膜中的温度独立的霍尔系数:为单带传输提供证据
Yuecong Liu1, Mengjun Ou1, Yi Wang1
1National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, People's Republic of China.
概括
通过对La$_{3-x}$A$_x$Ni$_2$O$_7$薄膜的Sr和Ca注,抑制了电阻的上升和不稳定. 观察到孔载体行为,令人惊的温度独立的霍尔系数表明脱轨道.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- La$_{3-x}$A$_x$Ni$_2$O$_7$ (A = Sr,Ca) 薄膜是通过脉冲激光沉积合成的.
- 兴奋剂 La 网站与 Sr 和 Ca 引入洞载体.
- 温度依赖的电阻表现出低温上升和高温不稳定.
研究的目的:
- 为了研究Sr和Ca兴奋剂对La$_{3-x}$Ni$_2$O$_7$薄膜的电子特性的影响.
- 分析在高压氧气大气下化后的影响.
- 了解电荷载体的行为及其温度依赖性.
主要方法:
- 脉冲激光沉积用于薄膜合成.
- 取决于温度的电阻测量.
- 霍尔效应测量.霍尔效应测量.
- 在高压氧气大气下进行后化.
主要成果:
- 通过Sr和Ca的兴奋剂,成功地制造了孔兴奋的La$_{3-x}$A$_x$Ni$_2$O$_7$薄膜.
- 后回火抑制了低温电阻的上升,并消除了高温的不稳定性.
- 霍尔效应测量揭示了孔电荷载体,其密度明显高于未使用过的薄膜.
- 霍尔系数在测量范围显示出出意想不到的温度独立性.
结论:
- 观察到的温度独立的霍尔系数表明没有多频带效应.
- 结果可能表明d_{x^2-y^2}$和d_{z^2}$轨道的脱,或者一个非常平的d_{z^2}$带有重质量.
- 这与原始样本中费米能量附近的结合$d_{z^2}$带的刚性带图像相矛盾.
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