Ab initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applications

Handle URI:
http://hdl.handle.net/10754/552784
Title:
Ab initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applications
Authors:
Amin, B.; Ahmad, Iftikhar; Maqbool, M.; Goumri-Said, S.; Ahmad, R.
Abstract:
A theoretical study of Al1−xGaxN, based on the full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap,optical properties, and nonlinear behavior of the compound with the change in the Ga concentration. It is found that the bandgap decreases with the increase in Ga. A maximum value of 5.50 eV is determined for the bandgap of pure AlN, which reaches a minimum value of 3.0 eV when Al is completely replaced by Ga. The static index of refraction and dielectric constant decreases with the increase in the bandgap of the material, assigning a high index of refraction to pure GaN when compared to pure AlN. The refractive index drops below 1 for higher energy photons, larger than 14 eV. The group velocity of these photons is larger than the vacuum velocity of light. This astonishing result shows that at higher energies the optical properties of the material shifts from linear to nonlinear. Furthermore, frequency dependent reflectivity and absorption coefficients show that peak values of the absorption coefficient and reflectivity shift toward lower energy in the ultraviolet (UV) spectrum with the increase in Ga concentration. This comprehensive theoretical study of the optoelectronic properties predicts that the material can be effectively used in the optical devices working in the visible and UV spectrum.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Ab initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applications 2011, 109 (2):023109 Journal of Applied Physics
Journal:
Journal of Applied Physics
Issue Date:
19-Jan-2011
DOI:
10.1063/1.3531996
ARXIV:
arXiv:1011.1573
Type:
Article
ISSN:
00218979
Additional Links:
http://scitation.aip.org/content/aip/journal/jap/109/2/10.1063/1.3531996; http://arxiv.org/abs/1011.1573
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorAmin, B.en
dc.contributor.authorAhmad, Iftikharen
dc.contributor.authorMaqbool, M.en
dc.contributor.authorGoumri-Said, S.en
dc.contributor.authorAhmad, R.en
dc.date.accessioned2015-05-14T07:16:53Zen
dc.date.available2015-05-14T07:16:53Zen
dc.date.issued2011-01-19en
dc.identifier.citationAb initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applications 2011, 109 (2):023109 Journal of Applied Physicsen
dc.identifier.issn00218979en
dc.identifier.doi10.1063/1.3531996en
dc.identifier.urihttp://hdl.handle.net/10754/552784en
dc.description.abstractA theoretical study of Al1−xGaxN, based on the full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap,optical properties, and nonlinear behavior of the compound with the change in the Ga concentration. It is found that the bandgap decreases with the increase in Ga. A maximum value of 5.50 eV is determined for the bandgap of pure AlN, which reaches a minimum value of 3.0 eV when Al is completely replaced by Ga. The static index of refraction and dielectric constant decreases with the increase in the bandgap of the material, assigning a high index of refraction to pure GaN when compared to pure AlN. The refractive index drops below 1 for higher energy photons, larger than 14 eV. The group velocity of these photons is larger than the vacuum velocity of light. This astonishing result shows that at higher energies the optical properties of the material shifts from linear to nonlinear. Furthermore, frequency dependent reflectivity and absorption coefficients show that peak values of the absorption coefficient and reflectivity shift toward lower energy in the ultraviolet (UV) spectrum with the increase in Ga concentration. This comprehensive theoretical study of the optoelectronic properties predicts that the material can be effectively used in the optical devices working in the visible and UV spectrum.en
dc.relation.urlhttp://scitation.aip.org/content/aip/journal/jap/109/2/10.1063/1.3531996en
dc.relation.urlhttp://arxiv.org/abs/1011.1573en
dc.rightsArchived with thanks to Journal of Applied Physicsen
dc.titleAb initio study of the bandgap engineering of Al1−xGaxN for optoelectronic applicationsen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalJournal of Applied Physicsen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionDepartment of Chemistry, Hazara University, Mansehra 21300, Pakistanen
dc.contributor.institutionDepartment of Physics and Astronomy, Ball State University, Muncie, Indiana 47306, USAen
dc.contributor.institutionDepartment of Chemistry, Hazara University, Mansehra 21300, Pakistanen
dc.identifier.arxividarXiv:1011.1573en
kaust.authorGoumri-Said, Sourayaen
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