Anisotropic Terahertz Emission from Bi2Se3 Thin Films with Inclined Crystal Planes

被引：1
作者：
Sun Young Hamh
Soon-Hee Park
Jeongwoo Han
Jeong Heum Jeon
Se-Jong Kahng
Sung Kim
Suk-Ho Choi
Namrata Bansal
Seongshik Oh
Joonbum Park
Jun Sung Kim
Jae Myung Kim
Do Young Noh
Jong Seok Lee
机构：
[1] Gwangju Institute of Science and Technology,Department of Physics and Photon Science, School of Physics and Chemistry
[2] Korea University,Department of Physics
[3] Kyung Hee University,Department of Applied Physics, College of Applied Science
[4] Rutgers,Department of Electrical and Computer Engineering
[5] The State University of New Jersey,Department of Physics and Astronomy
[6] Rutgers,Department of Physics
[7] The State University of New Jersey,undefined
[8] Pohang University of Science and Technology,undefined
[9] Advanced Light Source,undefined
[10] Lawrence Berkeley National Laboratory,undefined
来源：
Nanoscale Research Letters | 2015年 / 10卷
关键词：
Topological insulator; Bi; Se; Thin film; Terahertz emission; 78.68.+m; 68.37.-d; 73.22.-f;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
We investigate the surface states of topological insulator (TI) Bi2Se3 thin films grown on Si nanocrystals and Al2O3 substrates by using terahertz (THz) emission spectroscopy. Compared to bulk crystalline Bi2Te2Se, film TIs exhibit distinct behaviors in the phase and amplitude of emitted THz radiation. In particular, Bi2Se3 grown on Al2O3 shows an anisotropic response with a strong modulation of the THz signal in its phase. From x-ray diffraction, we find that the crystal plane of the Bi2Se3 films is inclined with respect to the plane of the Al2O3 substrate by about 0.27°. This structural anisotropy affects the dynamics of photocarriers and hence leads to the observed anisotropic response in the THz emission. Such relevance demonstrates that THz emission spectroscopy can be a sensitive tool to investigate the fine details of the surface crystallography and electrostatics of thin film TIs.
引用
收藏
相关论文
共 215 条
[1]  
Fu L(2007)Topological insulators in three dimensions Phys Rev Lett 98 106803-974
[2]  
Kane CL(2008)A topological Dirac insulator in a quantum spin Hall phase Nature 452 970-922
[3]  
Mele EJ(2009)Observation of unconventional quantum spin textures in topological insulators Science 323 919-198
[4]  
Hsieh D(2010)The birth of topological insulators Nature 464 194-229
[5]  
Qian D(2010)C.L.: topological insulators Rev Mod Phys 82 3045-1918
[6]  
Wray L(2010)The quantum spin Hall effect and topological insulators Phys Today 63 33-588
[7]  
Xia Y(2010)Structure of the (0001) basal twin boundary in Bi J Appl Phys 108 043517-257
[8]  
Hor YS(2011)Te Appl Phys Lett 99 013111-1160
[9]  
Cava RJ(2011)Molecular beam epitaxy and characterization of thin Bi Thin Solid Films 520 224-808
[10]  
Hasan MZ(2012)Se Cryst Growth Des 12 1913-24
12345678910