arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1208.4071cond-mat.mtrl-sci
收藏

金属有机化学气相沉积法制备拓扑绝缘体Bi2Te3薄膜

Topological insulator Bi2Te3 films synthesized by metal organic chemical vapor deposition

Helin Cao, Rama Venkatasubramanian, Chang Liu, Jonathan Pierce, Haoran Yang, M. Zahid Hasan, Yue Wu, Yong P. Chen

摘要:

拓扑绝缘体(TI)材料例如Bi 2 Te 3和Bi 2Se 3最近吸引了强烈的兴趣。大规模、高质量的TI薄膜对于开发TI基器件应用是重要的。本文采用金属有机化学气相沉积(MOCVD)方法在GaAs(001)衬底上制备了Bi 2 Te 3薄膜,并通过X射线衍射(XRD)、拉曼光谱、角分辨光电子能谱(ARPES)和电子输运测量等方法对薄膜的结构和电子性质进行了研究。ARPES测量的电子能带结构清晰地揭示了具有单一Dirac锥的特征拓扑表面态(SS),证实了MOCVD Bi 2 Te 3薄膜的TI性质.电阻率和霍尔效应测量表明,体载流子迁移率相对较高,在300 K时约为350 cm^2/Vs,在15 K时约为7,400 cm^2/Vs。我们还测量了薄膜的塞贝克系数。我们的示范高品质的拓扑绝缘体薄膜生长的一个简单的和可扩展的方法是利益的基础研究和实际应用的热电和TI材料。

英文摘要:

Topological insulator (TI) materials such as Bi2Te3 and Bi2Se3 have attracted strong recent interests. Large scale, high quality TI thin films are important for developing TI-based device applications. In this work, structural and electronic properties of Bi2Te3 thin films deposited by metal organic chemical vapor deposition (MOCVD) on GaAs (001) substrates were characterized via X-ray diffraction (XRD), Raman spectroscopy, angle-resolved photoemission spectroscopy (ARPES), and electronic transport measurements. The characteristic topological surface states (SS) with a single Dirac cone have been clearly revealed in the electronic band structure measured by ARPES, confirming the TI nature of the MOCVD Bi2Te3 films. Resistivity and Hall effect measurements have demonstrated relatively high bulk carrier mobility of ~350 cm^2/Vs at 300K and ~7,400 cm^2/Vs at 15 K. We have also measured the Seebeck coefficient of the films. Our demonstration of high quality topological insulator films grown by a simple and scalable method is of interests for both fundamental research and practical applications of thermoelectric and TI materials.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑