量子自旋霍尔效应通常存在于二维拓扑绝缘体中, 其具有受拓扑保护的无耗散螺旋边界态. 2014年, 理论预言单层1T' 相过渡金属硫族化合物是一类新型的二维量子自旋霍尔绝缘体. 其中, 以单层1T'-WTe 2为代表的材料体系具有原子结构稳定、体带隙显著、拓扑性质易于调控等许多独特的优势, 对低功耗自旋电子器件的发展具有...
单层1T′-WTe钛酸锶分子束外延扫描隧道显微镜电子结构应变二维层状过渡金属硫族化合物(Transition metal dichalcogenides,TMDs)材料因其具有能隙而被认为是可超越石墨烯的新型量子薄膜材料,从而激起了新一轮的研究热潮.二碲化钨(WTe2)属于TMDs的一种,近年来其新奇的物理,化学和量子特性被广泛研究,当薄膜厚度减小至单层...
研究内容:团队借助高分辨扫描隧道显微镜和准粒子干涉技术,精确表征了单层1T’-WTe2的能带结构,确定其为半金属型能带,解决了一直以来存在的争议。 文献信息:Observation of Coulomb gap in the quantum spin Hall candidate single-layer 1T’-WTe2(Nature Communications,2018,DOI:10.1038/s41467-018-06635-x)[原文链...
由于1T′和1H之间的能垒较低,通过控制碲化速度,可以很容易地使用CVD生长MoTe2和WTe2,如图8a所示。在快速碲化过程中,沉积膜中内置的应变或富Te空位稳定了1T′相碲化物。此外,前驱体影响TMD结构。采用旋转镀膜的方法,将含有钼酸钠...
Monolayer WTe2, known for its intriguing properties as a quantum spin Hall insulator, presents significant challenges for high-quality epitaxial film growth. These difficulties primarily arise from the low mobility of W on the substrate and the reduced reaction rate between W and Te. This study ...
Notably, it is twice as large as that of the related 2D TI WTe217. The thermal energy kBT is 25 meV at room temperature, and semiconductors must have a gap greater than about 4kBT = 100 meV in order to be useful. Based on this criterion, 1T′ WSe2 would be an excellent...
电子工程系的许建斌教授(共同通讯作者)合作通过使用普通盐(NaCl或KCl)作为生长促进剂,结合低成本可溶性钼酸铵四水合物(NH4)6Mo7O24•4H2O和钨酸铵水合物(NH4)10W12O41•xH2O分别作为Mo源和W源,使用常压化学气相沉积(APCVD)方法,生长出高质量、大面积单层和少层1T’相MoTe2(长度〜1mm)和WTe2(长度〜350...
1T'-WS2与空气敏感的拓扑绝缘体1T'-WTe2等结构。印刷的薄膜在室温下为金属,在7.3 K以下为超导,在面内和面外上临界磁场为30.1和5.3 T时表现出强烈的各向异性非常规超导行为,并且在环境条件下至少稳定30天。本文的研究结果表明,化学处理可以使以前只在实验室研究的非平凡2D材料成为商业可用。
Our results establish monolayer 1T'-WTe2 as a new class of QSH insulator with large bandgap in a robust two-dimensional materials family of transition metal dichalcogenides (TMDCs).Nature PhysicsShujie Tang, Hyejin Ryu, Juan Jiang, Zahid Hussain, Sung-Kwan MoShujie Tang, Zhi Liu, Xiaoming ...
In this study, we employ the QPI-STS/STM to detailedly investigate the electronic structure of single-layer 1T’-WTe2. At first, we clarify that the conduction bands (Tep) cross the Fermi level along the Y–Γ–Y direction, and the energy of their bottoms is lower than the top of the...