Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (12): 2805-2813.doi: 10.3866/PKU.WHXB20112805


Electronic Structures and Optical Properties of CuAlX2 (X=S, Se, Te) Semiconductors with a Chalcopyrite Structure

ZHOU He-Gen1, CHEN Hong1, CHEN Dong1, LI Yi1,2, DING Kai-Ning1, HUANG Xin1,3, ZHANG Yong-Fan1   

  1. 1. College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, P. R. China;
    2. State Key Laboratory Breeding Base of Photocatalysis, Fuzhou 350002, P. R. China;
    3. State Key Laboratory of Structural Chemistry, Fuzhou 350002, P. R. China
  • Received:2011-07-26 Revised:2011-09-28 Published:2011-11-25
  • Contact: ZHANG Yong-Fan
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (90922022) and Science and Technology Development Fund of Fuzhou University, China (2008-XQ-07).

Abstract: Density functional theory (DFT) based on the pseudo-potential plane wave basis set was used to investigate the electronic structures and optical properties of CuAlX2 (X=S, Se, Te) crystals with a chalcopyrite structure. The results indicate that these compounds have a similar band structure and the bandgap decreases from S to Te. Except for the static birefringence, which is just opposite to a change in the bandgap, the static dielectric constant, refractive index and second harmonic generation (SHG) coefficient d36 of this series of compounds increased from S to Te. The SHG response of the three semiconductors can be attributed to transitions from the occupied bands near the top of the valence band to the unoccupied bands that are contributed to by the p states of the Al and X atoms. Among the three crystals, the optical properties of the CuAlTe2 crystal are better than those of CuAlS2 and CuAlSe2 crystals except that the corresponding static birefringence is too small.

Key words: Density functional theory, Electronic structure, Optical property, Second harmonic generation, Chalcopyrite