Ab initio study of the linear and nonlinear optical properties of chalcopyrite CdGeAs{sub 2}

Journal Article · Sun Jan 15 00:00:00 EST 2012 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.10.014· OSTI ID:21612881

You, Yu ^[1]; Shifu, Zhu ^[1]; Tao, Gao ^[2]; Haijun, Hou; Zhiyu, He ^[1]

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1. College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China)
2. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China)

We present an ab initio theoretical study of the electronic, linear and nonlinear optical properties of CdGeAs{sub 2} using a pseudopotential plane-wave method. Specifically, we evaluate the band structure, density of states, charge density, the dielectric function {epsilon}({omega}) and the second harmonic generation response susceptibility {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) over a large frequency range. As LDA underestimates the band gap, we have applied the GW approximation method to calculate the quasiparticle band structure and obtain an energy band gap in agreement with experiment. In this case the opening of the gap due to the GW correction can be used as scissor shift to calculate the linear and nonlinear optical properties. The intra- and inter-band contributions to the imaginary part of {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) are presented over a broad energy range. It is found that the small energy gap semiconductor CdGeAs{sub 2} has larger values of {epsilon}{sub 1}(0) and {chi}{sub 312}{sup (2)}(0) than other chalcopyrite structures. - Graphical abstract: Calculated total imaginary part of {chi}{sub 312}{sup (2)}(-2{omega};{omega},{omega}) spectra along with the intra-(2{omega})/(1{omega}) and inter-(2{omega})/(1{omega}) band contributions. Highlights: Black-Right-Pointing-Pointer We find that the charge density around the cation Cd of CdGeAs{sub 2} is spherical. Black-Right-Pointing-Pointer We do not have to rely on experimental gap to determine the self-energy. Black-Right-Pointing-Pointer It is the first time we have calculated the SHG susceptibility using pseudopotential plane-wave. Black-Right-Pointing-Pointer The SHG susceptibility beyond zero frequency was calculated.

• OSTI ID: 21612881
• Journal Information: Journal of Solid State Chemistry, Vol. 185; Other Information: DOI: 10.1016/j.jssc.2011.10.014; PII: S0022-4596(11)00542-1; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
APPROXIMATIONS
CATIONS
CHALCOPYRITE
CHARGE DENSITY
DENSITY
ENERGY GAP
ENERGY RANGE
FREQUENCY RANGE
HARMONIC GENERATION
NONLINEAR PROBLEMS
OPTICAL PROPERTIES
SELF-ENERGY
SEMICONDUCTOR MATERIALS
SPECTRA
CALCULATION METHODS
CHARGED PARTICLES
ENERGY
FREQUENCY MIXING
IONS
MATERIALS
MINERALS
PHYSICAL PROPERTIES
SULFIDE MINERALS