We report the experimental observation of Landau quantization of molecular beam epitaxy grown Sb2Te3 thin films by a low-temperature scanning tunneling microscope. Different from all the reported systems, the Landau quantization in Sb2Te3 topological insulator is not sensitive to the intrinsic substitutional defects in the films. As a result, a nearly perfect linear energy dispersion of surface states as 2D massless Dirac fermion system is achieved. We demonstrate that 4 quintuple layers are the thickness limit for Sb2Te3 thin film being a 3D topological insulator. The mechanism of the Landau level broadening is discussed in terms of enhanced quasiparticle lifetime.
Evolution from Landau Quantization to Discrete Scale Invariance Revealed by Quantum Oscillations in Topological Materials
Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Center for Neutron Science and Technology, School of Physics, Sun Yet-sen University（中山大学物理学院）；International Center for Quantum Materials, School of Physics, Peking University（北京大学物理学院）；School of Physical Science and Technology, ShanghaiTech University（上海科技大学物理科学与技术学院）；Wuhan National High Magnetic Field Center, Huazhong University of Science & Technology（华中科技大学武汉国家强磁场中心）；Quantum Science Center of Guangdong–Hong Kong–Macao Greater Bay Area (Guangdong)（粤港澳大湾区量子科学中心（广东））；Center for Advanced Quantum Studies, School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院前沿量子研究中心）；Hefei National Laboratory（合肥国家实验室）；Collaborative Innovation Center of Quantum Matter（量子物质协同创新中心）
Landau quantization of $C_3$ high-fold fermions in honeycomb lattices
International Iberian Nanotechnology Laboratory (INL)（伊比利亚纳米技术国际实验室）；Department of Physics and I3N, University of Aveiro（阿威罗大学物理系及I3N）；Departamento de Física, Universidad de Alicante（阿利坎特大学物理系）
Scalable Sondheimer oscillations driven by commensurability between two quantizations
Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology（华中科技大学物理学院）；Laboratoire de Physique et d’Etude de Matériaux (CNRS) ESPCI Paris, PSL Research University（巴黎高等物理化工大学CNRS物理与材料研究实验室）；Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area（粤港澳大湾区量子科学中心）
Landau Quantization and Quasiparticle Interference in the Three-Dimensional Dirac Semimetal Cd3As2
凝聚态物质系统提供了一个丰富的设置，实现狄拉克和马约拉纳费米子激发和可能性，操纵它们在材料中的潜在应用。最近，有人提出，外尔费米子，这是手性，无质量的粒子，可以出现在某些块体材料或拓扑绝缘体多层膜，并可以产生不寻常的输运性质，如电荷泵驱动的手性异常。一对外尔费米子受到晶体对称性的保护，有效地形成了一个无质量的狄拉克费米子，已经被预测在一些被称为三维（3D）狄拉克半金属的候选材料中出现低能激发。在这里，我们报告扫描隧道显微镜（STM）测量在亚开尔文温度和高磁场上的一个有前途的主机材料，II-V族半导体Cd 3 As 2。我们的研究提供了第一个原子尺度的探测Cd 3As 2，表明缺陷主要影响的价带，与超高迁移率载流子在导带中的观察一致。通过结合朗道能级谱和准粒子干涉（QPI），我们区分了一个大的自旋分裂的导带在磁场和其扩展的Dirac-like色散高于预期的制度。与我们的实验结果相一致的模型能带结构表明，对于一个特定的取向的所施加的磁场，外尔费米子的低能量激发在Cd 3 As 2。
