Electronic and optical properties of GaS: A first-principles study

Abstract

The electronic band structure and optical properties of hexagonal GaS are investigated using the density functional theory. The calculated band structure shows that the crystal has an indirect band gap with the value of 1.54 eV in the Brillouin zone at the  Γ→M. The structural optimization has been performed using the generalized gradient approximation (GGA) and the local density approximation (LDA). The calculated structure optimization of GaS has been compared with the experimental results and has been found to be in good agreement with each other. Furthermore, the linear photon-energy-dependent dielectric functions and some optical constants such as energy-loss functions for volume and surface, extinction, reflectivity and absorption coefficients, refractive index and effective number of valence electrons per unit cell participating in the interband transitions have been calculated.  

 

Keywords

• Density functional theory
• local density approximation
• gradient and other corrections; Optical properties; Electronic structure; Optical constants.

References

1. Yee, K.A., Albright, A., “Bonding and structure of gallium thallium selenide (GaTlSe2)”, J. Am. Chem. Soc., 113: 6474-6478 (1991).
2. Kyazym-zade, A.G., Mekhtieva, R.N., Akhmedov A.A.,Sov. Phys. Semicond., 25: 840 (1992).
3. Mekhtiev, N.M., Rud, Yu V., Salaev, E., Yu., Sov. Phys. Semicond., 12: 924 (1978).
4. Aulich, E., Brebner, J.L., Mooser, E., “Indirect Energy Gap in GaSe and GaS”, Phys. Status Solid, 31: 129-131 (1969).
5. Irwin, J.C., Hoff, R.M., Clayman, B.P., Bromley, R.A., “Long wavelength lattice vibrations in GaS and GaSe”, Solid State Commun., 13: 1531-1536 (1973).
6. Lucazeau, G., “Vibrational spectra of a GaS single crystal”, Solid State Commun., 18: 917-922 (1976).
7. Gasanly, N.M., “Effect of Crystal Disorder on Line Width Broadening of Phonon Modes in GaS1-x Sex Layered Mixed Crystals”, Crystal Research and Technolology, 38: 962-967 (2003).
8. Gasanly, N.M., Goncharov, A.F., Melnik, N.N., Ragimov, A.S., “Optical Phonons in GaS1-xSex Layer Mixed Crystals”, Phys. Stat. Sol. (b), 120: 137-147 (1983).

9. Gasanly, N.M., Aydinli, A., Ozkan, H., Kocabas, C., “Temperature Dependence of the First-order Raman Scattering in GaS Layered Crystals”, Solid State Commun., 116: 147-151 (2000).
10. Gasanly, N.M., Aydinli, A., “Low-temperature Raman Scattering Spectra of GaSexS1-x Layered Mixed Crystals”, Crystal Res. Technol., 37: 1011- 1017 (2002).
11. Gasanly, N.M., “Compositional dependence of the Raman line shapes in GaSxSe1-x layered mixed crystals”, J. Raman Spectroscopy, 36: 879-883 (2005).
12. Riede, V., Neumann, H., Nguyen, H. X., Sobotta, H., Levy, F., “Polarization-dependent infrared optical properties of GaS”, Physica B, 100: 355- 363 (1980).
13. Powell, B.M., Jandl, S., Brebner, J.L., Levy, F., “Anisotropic phonon dispersion in GaS”, J. Phys. C: Solid State Phys., 10: 3039 (1977).
14. Polian, A., Besson, J.M., Grimsditch, M., Vogt, H., “Elastic properties of GaS under high pressure by Brillouin scattering”, Phys. Rev. B, 25: 2767-2775 (1982).
15. Gasanly, N.M., Aydinli, A., Yuksek, N.S.,
16. Salihoglu, O., “Trapping Centers in Undoped GaS Layered Single Crystals”, Applied Physics A - Materials Science and Processing, 77: 603-606 (2003).
17. Akhundov, G., Aksyanov, I.G., Gasumov, G.M., Sov. Phys. Semicon., 3: 767 (1969).
18. Karaman, M.I., Mushinskii, V.P., Sov. Phys.
19. Semicond., 4: 662 (1970).
20. Cingolani, A., Minafra, A., Tantalo, P., Paorici, C., “Edge emission in GaSe and GaS”, Phys. Status Solidi A, 4: K83-K85 (1971).
21. Aono, T., Kase, K., Kinoshita, A., “Near-blue
22. photoluminescence of Zn-doped GaS single crystals”, J. Appl. Phys., 74: 2818-2820 (1993).
23. Mercier, A., Mooser, E., Voitchovsky, J.P., “Near edge optical absorption and luminescence of GaSe, GaS and of mixed crystals”, Journal of Lumin., 7: 241-266 (1973).
24. Mercier, A., Voitchovsky, J.P., “Donor-acceptor pair recombination and phonon replica in GaSxSe1−x”, J. Phys. Chem. Solids, 36: 1411-1417 (1975).
25. Karaman, M.I., Mushinskii, V.P., Sov. Phys.
26. Semicond., 4: 464 (1970).
27. Aydinli, A., Gasanly, N.M., Goksen, K., “Donor- acceptor Pair Recombination in Gallium Sulfide”, J. Appl. Phys., 88:7144-7149 (2000).
28. Kuhn, A., Bourdan, A., Rigoult, J., Rimsky, A., “Charge-density analysis of GaS”, Phys. Rev. B, 25: 4081-4088 (1982). [25] Fuchs, M., Scheffler, M., “Ab initio pseudopotentials for electronic structure calculations of poly-atomic systems using density- functional theory”, Comput. Phys. Commun., 119: 67-98 (1999). [26] Troullier, N., Martins, J.L., “Efficient pseudopotentials for plane-wave calculations”, Phys. Rev. B, 43: 1993-2006 (1990).
29. Perdew, J.P., Burke, K., Ernzerhof, M., “Generalized Gradient Approximation Made Simple”, Phys. Rev. Lett., 77: 3865-3868 (1996).
30. Perdew, J.P., Wang, Y., “Accurate and simple analytic representation of the electron-gas correlation energy”, Phys. Rev. B, 45: 13244- 13249 (1992).
31. Payne, M.C., Teter, M.P., Allan, D.C., Arias, T.A., Joannopoulos, J.D., “Iterative minimization techniques for ab initio total-energy calculations: molecular dynamics and conjugate gradients”, Rev. Mod. Phys., 64: 1045-1097 (1992).
32. Gonze, X., Beuken, J.M., Caracas, R., Detraux, F., Fuchs, M., Rignanese, G.M., Sindic, L., Verstrate, M., Zerah, G., Jollet, F., Torrent, M., Roy, A., Mikami, M., Ghosez, P., Raty, J.Y., Allan, D.C., “First-principle computation of material properties: the ABINIT software project”, Comput. Mater. Sci., 25: 478-492 (2002).
33. Kohn, W., Sham, L.J., “Self-Consistent Equations Including Exchange and Correlation Effects”, Phys. Rev., 140: A1133-A1138 (1965).
34. Monkhorst, H.J., Pack, J.D., “Special points for Brillouin-zone integrations”, Phys. Rev. B, 13: 5188-5192 (1976).
35. Akkus, H., Mamedov, A.M., Kazempur, A.,
36. Akbarzadeh, H., “Band structure and optical properties of antimony-sulfobromide: dendity functional calculation”, Central European Journal of Physics, 6: 64-75 (2008).
37. Hughes, J.L.P., Sipe, J.E., “Calculation of second- order optical response in semiconductors”, Phys. Rev. B, 53:10751-10763 (1996).
38. Philipp, H.R., Ehrenreich, H., “Optical properties of semiconductors”, Phys. Rev., 129: 1550-1560 (1963).