结构扭曲的持续性和散带拉什巴分裂在SnTe上方的铁电临界温度以上
Frédéric Chassot1, Aki Pulkkinen1,2, Geoffroy Kremer1,3
1Department of Physics and Fribourg Center for Nanomaterials, Université de Fribourg, Fribourg 1700, Switzerland.
Nano letters
|December 18, 2023
概括
这项研究表明,铁电半导体锡化 (SnTe) 呈现出持续的散带分裂,超过其临界温度. 这一发现挑战了SnTe.Te上拓表面状态的存在.
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
- 固态物理 固态物理
背景情况:
- 锡化物 (SnTe) 被认为是一种拓晶体绝缘体.
- SnTe的表面状态已被广泛使用角度分辨光发射光谱学 (ARPES) 研究.
- 铁电过渡对SnTe散装电子结构的影响仍然不太被探索.
研究的目的:
- 研究α-SnTe的低能电子结构.
- 追踪散装状态Rashba在铁电过渡过程中分裂的温度依赖.
- 澄清SnTe.Te.中拓表面状态形成的条件.
主要方法:
- 角度分辨率光辐射光谱学 (ARPES).
- 电子带结构的温度依赖测量.
主要成果:
- 观察到持续的Rashba带分裂在α-SnTe的散装状态到室温.
- 裂变在铁电临界温度 (Tc ≈ 110 K) 以上仍然存在.
- 这种行为表明一个秩序-混乱组件,涉及Tc以上波动的二极体.
结论:
- 观察到的持续的带分裂表明Tc以上的波动二极体,与秩序-混乱相位过渡一致.
- 与一些文献相反,在这些条件下,拓表面状态不太可能存在于SnTe的 (111) 表面.
- 这项研究修订了对SnTe电子结构和拓性质的理解.
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