Electronic Structure and Photoelectric Properties ofZnTe under High Pressure
-
摘要: 应用第一性原理平面波赝势计算方法，研究了闪锌矿ZnTe晶体在外界压力下的电子结构和光电性质, 并计算了介电函数和光学吸收系数随压力的变化情况。结果表明：在高压作用下，Te原子和Zn原子的态密度分布都向低能量方向移动，分布范围增大，Te 5p和Zn 3d电子轨道杂化变强。随着压力的增大，直接带隙逐渐增大，而间接带隙逐渐变小。当压力为10.7 GPa时，能带结构从直接带隙转变为间接带隙结构。压力增大，有利于Te 5p与Zn 3d电子间的跃迁，光吸收系数增大，产生更多的电子-空穴对，材料导电能力增强。Abstract: The electrons structure and photoelectric properties of zinc-blende structural ZnTe were investigated under high pressure, using first-principles plane-wave pseudo-potential method.The dielectric function and optical absorption coefficient were also predicted under high pressure.The results show that the distributions of density of states of Te and Zn atoms under high pressure shift towards lower energy direction and cover wider range.High pressure leads to stronger hybridization between Te 5p and Zn 3d electrons.The direct band gap increases gradually with pressure while the indirect band gap decreases.The direct band gap structure becomes an indirect one when the ambient pressure reaches 10.7 GPa.High pressure helps the transitions between Te 5p and Zn 3d electrons.The optical absorption coefficient increases, which leads to more electron-hole pairs and enhances the conductivity.
-
图 3 不同压力下Te原子的s和p电子的态密度
Figure 3. Density of states of s and p electrons of Te under different pressures
图 4 不同压力下Zn原子的s和d电子的态密度
Figure 4. Density of states of s and d electrons of Zn under different pressures
表 1 ZnTe在不同压力下的直接带隙和间接带隙
Table 1. Direct and indirect band gaps of ZnTe under different pressures
Pressure/
(GPa)E1/(eV) E2/(eV) Present Calc.[19] Calc.[20] Exp.[18] Present Calc.[19] Exp.[18] 0 1.39 1.28 1.10 2.39 2.45 2.11 3.30 1.0 1.48 1.35 - - 2.44 2.07 - 2.0 1.57 1.42 - - 2.42 2.04 - 3.0 1.66 1.49 - - 2.40 2.00 - 4.0 1.74 1.56 - - 2.39 1.97 - 5.0 1.82 1.63 - - 2.37 1.93 - 6.0 1.89 1.70 - - 2.35 1.90 - 7.0 1.96 1.77 - - 2.32 1.86 - 8.0 2.02 1.84 - - 2.28 1.82 - 9.0 2.08 1.91 - - 2.25 1.79 - 10.0 2.15 1.98 - - 2.21 1.76 - 10.7 2.19 - - - 2.19 - - 11.0 2.21 2.05 - - 2.18 1.72 - 12.0 2.26 2.12 - - 2.15 1.68 - Note:E1 and E2 represent the direct and indirect band gaps，respectively. 
下载: 导出CSV
-
[1] Mitchell D W, Das T P, Potzel W, et al. First-principles investigation of 67Zn isomer shifts in ZnF2 and the chalcogenides ZnO, ZnS, ZnSe, and ZnTe[J]. Phys Rev B, 1993, 48(22): 16449-16462. doi: 10.1103/PhysRevB.48.16449 [2] Bozzini B, Baker M A, Cavallotti P L, et al. Electrodeposition of ZnTe for photovoltaic cells[J]. Thin Solid Films, 2000, 361(2): 388-395. [3] Ishizaki T, Ohtomo T, Fuwa A. Structural, optical and electrical properties of ZnTe thin films electrochemically deposited from a citric acid aqueous solution[J]. J Phys D: Appl Phys, 2004, 37(2): 255-258. doi: 10.1088/0022-3727/37/2/014 [4] 邵军. Ti掺杂ZnTe体材料的优化光致发光光谱[J].物理学报, 2003, 52(7): 1743-1747.Shao J. Optimal photoluminescence spectrum from Ti-doped ZnTe[J]. Acta Physica Sinica, 2003, 52(7): 1743-1747. (in Chinese) [5] Sinyukov A M, Hayden L M. Generation and detection of terahertz radiation with multilayered electro-optic polymer films[J]. Opt Lett, 2002, 27(1): 55-57. doi: 10.1364/OL.27.000055 [6] Löffler T, Hahn T, Thomson M, et al. Large-area electro-optic ZnTe terahertz emitters[J]. Opt Express, 2005, 13(14): 5353-5362. doi: 10.1364/OPEX.13.005353 [7] 王月.高压下ZnX(S、Se、Te)和TiO2的电学性质[D].长春: 吉林大学, 2010: 2-4.Wang Y. The electrical properties of ZnX(S, Se, Te)and TiO2 under high pressure[D]. Changchun: Jilin University, 2010: 2-4. (in Chinese) [8] Samara G A, Drickamer H G. Pressure induced phase transitions in some Ⅱ-Ⅵ compounds[J]. J Phys Chem Solids, 1962, 23(5): 457-461. doi: 10.1016/0022-3697(62)90086-0 [9] San-miguel A, Polian A, Gauthier M, et al. ZnTe at high pressure: X-ray-absorption spectroscopy and X-ray-diffraction studies[J]. Phys Rev B, 1993, 48(12): 8683-8693. doi: 10.1103/PhysRevB.48.8683 [10] Franco R, Mori-Sanchez P, Recio J M, et al. Theoretical compressibilities of high-pressure ZnTe polymorphs[J]. Phys Rev B, 2003, 68(19): 195208-195212. doi: 10.1103/PhysRevB.68.195208 [11] 吕冉, 高涛, 李喜波, 等.闪锌矿ZnTe高温高压下的弹性及热力学性质[J].物理化学学报, 2010, 26(1): 13-17.Lü R, Gao T, Li X B, et al. Elastic and thermodynamic properties of zinc-blende ZnTe under high temperature and pressure[J]. Acta Physico-Chimica Sinica, 2010, 26(1): 13-17. (in Chinese) [12] Perdew J P, Levy M. Physical content of the exact Kohn-Sham orbital energies: Band gaps and derivative discontinuities[J]. Phys Rev Lett, 1983, 51(20): 1884-1887. doi: 10.1103/PhysRevLett.51.1884 [13] 何开华, 郑广, 陈刚, 等.高压下氧化镉弹性性质、电子结构和光学性质的第一性原理研究[J].高压物理学报, 2007, 21(3): 299-304.He K H, Zheng G, Chen G, et al. First principles study of the elastic, electronic and optical properties of CdO under pressure[J]. Chinese Journal of High Pressure Physics, 2007, 21(3): 299-304. (in Chinese) [14] Kresse G, Hafner J. Ab initio molecular dynamics for liquid metals[J]. Phys Rev B, 1993, 47(1): 558-561. doi: 10.1103/PhysRevB.47.558 [15] Kresse G, Hafner J. Ab initio molecular-dynamics simulation of the liquid-metal-amorphous-semiconductor transition in germanium[J]. Phys Rev B, 1994, 49(20): 14251-14269. doi: 10.1103/PhysRevB.49.14251 [16] Kresse G, Furthmuller J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set[J]. Comput Mater Sci, 1996, 6(1): 15-50. doi: 10.1016/0927-0256(96)00008-0 [17] Nassour A. First-principles calculations of structural properties and lattice dynamics in ZnSexTe1-x alloys[J]. Comput Mater Sci, 2013, 77(1): 403-407. [18] Lempert R G, Hass K C, Ehrenreich H. Molecular coherent-potential approximation for zinc-blende pseudobinary alloys[J]. Phys Rev B, 1987, 36(2): 1111-1129. doi: 10.1103/PhysRevB.36.1111 [19] Khenata R, Bouhemadou A, Sahnoun M, et al. Elastic, electronic and optical properties of ZnS, ZnSe and ZnTe under pressure[J]. Comput Mater Sci, 2006, 38(1): 29-38. doi: 10.1016/j.commatsci.2006.01.013 [20] Sheetal S, Verma A S, Sarkar B K, et al. FP-LAPW+lo calculations for the structural, electronic, optical and mechanical properties of ZnX(X=S, Se and Te)[C]//Proceeding of the 56th DAE Solid Physics Symposium. Atlanta: American Institute of Physics, 2012: 849-850. [21] Stampfl C, van de Walle C G. Density-functional calculations for Ⅲ-Ⅴ nitrides using the local-density approximation and the generalized gradient approximation[J]. Phys Rev B, 1999, 59(8): 5521-5535. doi: 10.1103/PhysRevB.59.5521 [22] Karazhanov S Z, Ravindran P, Kjekshus A, et al. Electronic structure and optical properties of ZnX(X=O, S, Se, Te): A density functional study[J]. Phys Rev B, 2007, 75(15): 155104-155117. doi: 10.1103/PhysRevB.75.155104 [23] 黄昆, 韩汝琦.固体物理学[M].北京: 高等教育出版社, 1988: 438-440.Huang K, Han R Q. Solid-State Physics[M]. Beijing: Higher Education Press, 1988: 438-440. (in Chinese) [24] 沈学础.半导体光谱和光学性质[M].北京: 科学出版社, 1992: 7-10.Shen X C. Spectrum and Optical Property of Semiconductor[M]. Beijing: Science Press, 1992: 7-10. (in Chinese) [25] 冯晶, 肖冰, 陈敬超. CuInSe2电子结构与光学性质的第一性原理计算[J].物理学报, 2007, 56(10): 5990-5995.Feng J, Xiao B, Chen J C. Electronic and optical properties of CuInSe2 from ab-initio calculations[J]. Acta Physica Sinica, 2007, 56(10): 5990-5995. (in Chinese) [26] 郭建云, 郑广, 何开华, 等. Al, Mg掺杂GaN电子结构及光学性质的第一性原理研究[J].物理学报, 2008, 57(6): 3740-3746.Guo J Y, Zheng G, He K H, et al. First-principles study on electronic structure and optical properties of Al and Mg doped GaN[J]. Acta Physica Sinica, 2008, 57(6): 3740-3746. (in Chinese) [27] Adachi S. Optical Constants of Crystalline and Amorphous Semiconductors: Numerical Data and Graphical Information[M]. Boston: Kluwer Academic Publishers, 1999: 473-478. [28] Cui X Y, Hu T J, Yang J, et al. The electrical properties of ZnTe under high pressure and moderate temperature[J]. Phys Status Solidi C, 2011, 8(5): 1676-1679. doi: 10.1002/pssc.201000609 -
下载:
点击查看大图
图(9) / 表(1)
计量
- 文章访问数: 6584
- HTML全文浏览量: 2226
- PDF下载量: 281
