Chin. Phys. B ›› 2014, Vol. 23 ›› Issue (1): 17304-017304.doi: 10.1088/1674-1056/23/1/017304

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Ab initio study of structural, electronic and optical properties of ternary CdO1-xSex alloys using special quasi-random structures

Muhammad Rashida, Fayyaz Hussainb, Muhammad Imrana b, S. A. Ahmada, N. A. Noorc   

  1. a Department of Physics Simulation Lab, the Islamia University of Bahawalpur 63100, Pakistan;
    b Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan;
    c Department of Physics, University of the Punjab, Quaid-e-Azam Campus, Lahore 54590, Pakistan
  • 收稿日期:2013-04-16 修回日期:2013-06-23 出版日期:2013-11-12 发布日期:2013-11-12

Ab initio study of structural, electronic and optical properties of ternary CdO1-xSex alloys using special quasi-random structures

Muhammad Rashida, Fayyaz Hussainb, Muhammad Imrana b, S. A. Ahmada, N. A. Noorc   

  1. a Department of Physics Simulation Lab, the Islamia University of Bahawalpur 63100, Pakistan;
    b Department of Physics, Bahauddin Zakariya University, Multan 60800, Pakistan;
    c Department of Physics, University of the Punjab, Quaid-e-Azam Campus, Lahore 54590, Pakistan
  • Received:2013-04-16 Revised:2013-06-23 Online:2013-11-12 Published:2013-11-12
  • Contact: Fayyaz Hussain E-mail:fayyazhussain248@yahoo.com

摘要: The structural, electronic, and optical properties of binary CdO, CdSe, and their ternary CdO1-xSex alloys (0≤ x ≤ 1) in the rock salt and zinc blend phases have been studied by the special quasi-random structure (SQS) method. All the calculations are performed using full-potential linearized augmented plane wave plus local orbital’s (FP-LAPW+lo) method within the framework of density function theory (DFT). We use Wu–Cohen (WC) generalized gradient approximation (GGA) to calculate structural parameters, whereas both Wu–Cohen and Engel–Vosko (EV) GGA have been applied to calculate electronic structure of the materials. Our predicted results of lattice constant and bulk modulus show only a slight deviation from Vegard’s law for the whole concentrations. The obtained band structure indicates that for the rock-salt phase, the ternary alloys present semi-metallic behavior, while for the zinc blend phase, semiconductor behavior with direct bandgap is observed with decreasing order of x except for CdSe. Finally, by incorporating the basic optical properties, we discuss the dielectric function, refractive index, optical reflectivity, the absorption coefficient, and optical conductivity in terms of incident photon energy up to 14 eV. The calculated results of both binaries are in agreement with existing experimental and theoretical values.

关键词: density functional theory, structural, electronic, and optical properties

Abstract: The structural, electronic, and optical properties of binary CdO, CdSe, and their ternary CdO1-xSex alloys (0≤ x ≤ 1) in the rock salt and zinc blend phases have been studied by the special quasi-random structure (SQS) method. All the calculations are performed using full-potential linearized augmented plane wave plus local orbital’s (FP-LAPW+lo) method within the framework of density function theory (DFT). We use Wu–Cohen (WC) generalized gradient approximation (GGA) to calculate structural parameters, whereas both Wu–Cohen and Engel–Vosko (EV) GGA have been applied to calculate electronic structure of the materials. Our predicted results of lattice constant and bulk modulus show only a slight deviation from Vegard’s law for the whole concentrations. The obtained band structure indicates that for the rock-salt phase, the ternary alloys present semi-metallic behavior, while for the zinc blend phase, semiconductor behavior with direct bandgap is observed with decreasing order of x except for CdSe. Finally, by incorporating the basic optical properties, we discuss the dielectric function, refractive index, optical reflectivity, the absorption coefficient, and optical conductivity in terms of incident photon energy up to 14 eV. The calculated results of both binaries are in agreement with existing experimental and theoretical values.

Key words: density functional theory, structural, electronic, and optical properties

中图分类号:  (Surface states, band structure, electron density of states)

  • 73.20.At
78.20.Ci (Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity))