首页期刊信息编委及顾问期刊发行联系方式使用帮助常见问题ENGLISH
位置:首页 >> 正文
拉伸应变对单层MoTe2电子结构的影响
作者:赵旭1 陈鹏1 张芳2 
单位:1. 河南师范大学物理与电子工程学院  河南 新乡 453007  
关键词:第一性原理 二碲化钼 拉伸应变 电子结构 
分类号:O469
出版年,卷(期):页码:2016,44(7):942-947
DOI:
摘要:

采用基于密度泛函理论的第一性原理计算方法计算了单层MoTe2的能带结构和态密度,研究了拉伸应变对单层MoTe2电子结构的影响。计算结果表明:与单轴应变相比,双轴应变对Te–Te原子间距和Te–Mo–Te键角等晶格参数的影响更大,键长和键角的变化会影响原子不同轨道间的耦合强度,因此在调节单层MoTe2的带隙宽度时,施加双轴应变比单轴应变更有效。对单层MoTe2施加单轴应变后,其带隙宽度随着应变的增加缓慢减小,能带结构与未施加应变时相同,仍为直接带隙。而施加双轴应变后,单层MoTe2的带隙宽度明显变小,当应变接近6%时,其能带结构由直接带隙变为间接带隙。通过对投影电荷密度的分析,揭示了施加双轴拉伸应变时能带结构变化的根本原因。
 

The band structure and state density of monolayer MoTe2 were calculated by the first-principles method based on the density functional theory. The effect of tensile strain on the electronic structure of monolayer MoTe2 was investigated. The calculated results indicate that the biaxial strain has a greater effect on the lattice parameters of Te–Te distance and Te–Mo–Te bond angle rather than the uniaxial strain. The change of bond length and bond angle affects the coupling strength between different atom orbitals, therefore the biaxial strains are more effective than the uniaxial strains in modulating the bandgap of monolayer MoTe2. Under the uniaxial strains, the calculated bandgap decreases slightly as the strain increases, while the band structure is preserved and the monolayer MoTe2 remains as a semiconductor with a direct bandgap. Under the biaxial strains, the calculated bandgap decreases obviously as the strain increases, a certain biaxial strain (6%) results in the transition from direct to indirect gap for monolayer MoTe2. The fundamental reason for the change of band structure under the biaxial tensile strain was analyzed based on the further analysis of the projected charge density for monolayer MoTe2.
 

基金项目:
国家自然科学基金项目(1150409);河南省教育厅自然科学研究计划项目(2011A140018);河南省教育厅科学技术研究重点项目基础研究计划项目(14A140012);国家大学生创新创业训练计划资助项目(201510476043);河南省高等学校重点科研项目(15B140008)资助。
作者简介:
赵 旭(1979—),女,博士,副教授。
参考文献:

[1] LINDAHL N, MIDTVEDT D, SVENSSON J. Determination of the bending rigidity of graphene via electrostatic actuation of buckled membranes [J]. Nano Lett, 2012, 12(7): 3526–3531.
[2] GHOSH S, CALIZO I, TEWELDEBRHAN D. Extremely high thermal conductivity of graphene: Prospects for thermal management applications in nanoelectronic circuits [J]. Appl Phys Lett, 2008, 92: 151911–151913.
[3] GEIM A K, NOVOSELOV K S. The rise of graphene[J]. Nat Mater, 2007, 6: 183–191.
[4] PARK K H, LEE D, KIM J. defect-free, size-tunable graphene for high-performance lithium ion battery[J]. Nano Lett, 2014, 14(8): 4306–4313.
[5] DRESSELHAUS S, CHEN G, TANG M Y. New directions for low-dimensional thermoelectric materials[J]. Adv Mater, 2007, 19: 1043–1053.
[6] TANAKA H, OKUMIYA T, UEDA S K. Synthesis of molybdenum disulfide (MoS2) for lithium ion battery applications [J]. Mater Res Bull, 2009, 44: 1811–1815.
[7] ASPLENDIANI A, SUN L, ZHANG Y B. Emerging photoluminescence in monolayer MoS2[J]. Nano Lett, 2010, 10: 1271–1275
[8] TAKADA K, SAKURAI H, TAKAYAMA-MUROMACHI E. Superconductivity in two-dimensional CoO2 layers[J]. Nature, 2003, 422: 53–55.
[9] PUTHUSSERY J, SEEFELD S, BERRY N. Colloidal iron pyrite (FeS2) nanocrystal inks for thin-film photovoltaics[J]. Am Chem Soc, 2011, 133: 716–719.
[10] LEE C, LI Q, KALB W. Frictional characteristics of atomically thin sheets[J]. Science, 2010, 328: 76–80.
[11] SHISHIDOU T, FREEMAN A, ASAH R. Effect of GGA on the half-metallicity of the itinerant ferromagnet CoS2 [J]. Phys Rev B, 2001, 64: 180401(1–4).
[12] REED C A, CHEUNG S K. On the bonding of FeO2 in hemoglobin and related dioxygen complexes [J]. Proc Nat Acad Sci, 1977, 74: 1780–1784.
[13] LUO X, ZHAO Y Y, ZHANG J. Effects of lower symmetry and dimensionality on Raman spectra in two-dimensional WSe2[J]. Phys Rev B, 2013, 88: 195313(1–7).
[14] GRANT A J, GRIFFITHS T M, PITT G D. The electrical properties and the magnitude of the indirect Gap in the Semiconducting transition metal dichalcogenide layer crystals[J]. J Phys C: Solid State Phys, 1975, 8: L17–L23.
[15] CONAN A, DELAUNAY D, BONNET A. Temperature dependence of the electrical conductivity and thermoelectric power in MoTe2 single crystals[J]. Phys Status Solidi B, 1979, 94: 279–286.
[16] PRADHAN N R, RHODES D, FENG S. Field-effect transistors based on few-layered α-MoTe2[J]. ACS Nano, 2014, 8: 5911–5920. 
[17] RUPPERT C, ASLAN O B, HEINZ T F. Optical properties and band GaP of single- and few-Layer MoTe2 [J]. Nano Lett, 2014, 14(11): 6231–6236.
[18] LEE C, WEI X, KYSAR J W. Measurement of the elastic properties and intrinsic strength of monolayer graphene[J]. Science, 2008, 321(5887)): 385–388.
[19] BERTOLAZZI S, BRIVIO J, KIS A. Stretching and breaking of ultrathin MoS2 [J]. ACS Nano, 2011, 5(12): 9703–9709.
[20] COOPER R C, LEE C, MARIANETTI C A, et al. Nonlinear elastic behavior of two-dimensional molybdenum disulfide [J]. Phys Rev B, 2013, 87: 035423(1–11).
[21] CASTRO NETO A H, GUINEA F, PERES N M R. The electronic properties of graphene[J]. Rev Mod Phys, 2009, 81: 109–162.
[22] NOVOSELOV K S. Nobel Lecture: Graphene: Materials in the flatland [J]. Rev Mod Phys, 2011, 83: 837–849.
[23] BUTLER S Z, HOLLEN S M, CAO L. Progress, challenges, and opportunities in two-dimensional materials beyond graphene[J]. ACS Nano, 2013, 7(4): 2898–2926.
[24] XU M, LIANG T, SHI M. Graphene-like two-dimensional materials [J]. Chem Rev, 2013, 113(5): 3766–3798.
[25] CONLEY H J, WANG B, ZIEGLER J I. Bandgap engineering of strained monolayer and bilayer MoS2 [J]. Nano Lett, 2013, 13(8): 3626–3630.
[26] HE K, POOLE C, MAK K F. Experimental demonstration of continuous electronic structure tuning via strain in atomically thin MoS2[J]. Nano Lett, 2013, 13(6): 2931–2936.
[27] ZHU C R, WANG G, LIU B L. Strain tuning of optical emission energy and polarization in monolayer and bilayer MoS2[J]. Phys Rev B, 2013, 88(12): 121301(1–5).
[28] WU W, WANG L, LI Y. Piezoelectricity of single-atomic-layer MoS2 for energy conversion and piezotronics[J]. Nature, 2014, 514 (7523): 470–474.
[29] ZHU H, WANG Y, XIAO J. Observation of piezoelectricity in free-standing monolayer MoS2 [J]. Nat Nanotechnol, 2015, 10: 151–155.
[30] KRESSE G, FURTHMULLER J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set [J]. Phys Rev B, 1996, 54: 11169–11186.
[31] KRESSE G, JOUBERT J. From ultrasoft pseudopotentials to the projector augmented-wave method [J]. Phys Rev B, 1999, 59: 1758–1775.
 

服务与反馈:
文章下载】【加入收藏
中国硅酸盐学会《硅酸盐学报》编辑室
京ICP备10016537号-2
京公网安备 11010802024188号
地址:北京市海淀区三里河路11号    邮政编码:100831
电话:010-57811253  57811254    
E-mail:jccs@ceramsoc.com