Electronic structure of wurtzite TlxIn1−xN alloys

• Published in: Materials chemistry and physics 2017-09, Vol.198, p.209-213
• Main Author: Winiarski, M.J.
• Format: Article
• Language: English
• Subjects: ab-initio calculation; Alloys; Band gap; Crystal structure; Density; Density functional theory; Dilution; Electric properties; Electronic properties; Electronic structure; Energy gap; Lattice parameters; Nitrides; Optoelectronic devices; Semiconductor alloys; Spin-orbit interactions; Thallium; Wurtzite
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2017.06.005

The structural and electronic properties of wurtzite TlxIn1−xN materials have been investigated from first principles within the density functional theory (DFT). Band structures were obtained with the modified Becke-Johnson (MBJLDA) approach. A narrow band gap of 63 meV, induced by a strong spin-orbit coupling, is predicted in the hypothetical thallium nitride. The band gap inversion in TlN suggests that this compound is a promising candidate for a topological insulator. The lattice parameters of TlxIn1−xN alloys exhibit a linear behavior as a function of a Tl content x. An incorporation of Tl atoms in these systems leads also to a linear decrease of a band gap. For x>0.3 a very narrow energy gap, analogous to that of the pure TlN, is revealed. The band gap reduction of 26 meV/%Tl is comparable in value to those reported in the literature for dilute Bi-doped GaSb and InSb. The Tl-doped InN systems are promising materials for infrared optoelectronic devices. •Tl-doped InN systems are investigated by density-functional theory methods.•Structural and electronic properties of TlxIn1−xN alloys are studied.•A small lattice mismatch between TlxIn1−xN and InN systems is predicted.•A linear reduction of a band gap as a function of a Tl content is found.•TlxIn1−xN alloys are potential candidate materials for optoelectronic applications.