Electronic and optical properties of Sr₃X₂ (X=N, P, As, Sb and Bi) compounds: first principles study

ABSTRACT

Direct bandgap semiconductors are very essential to fulfil the demand for the advancement in optoelectronic devices. Therefore it is important to predict new potential candidates having such unique features. In current work, Sr₃X₂ (X=N, P, As, Sb and Bi) compounds have been reported for the first time by well trusted FP-APW+lo method. For the better prediction of the energy band gap, mBJ is used alongwith routine generalised gradient approximation (GGA). The results show small and direct energy band gaps at Γ-Γ symmetry points with magnitude in the range from 0.62 eV (Sr₃P₂) to zero energy band gap (Sr₃Bi₂). In partial density of state Sr-d state and X-p state are contributed in the band structure. The compounds show mostly covalent bonding nature. The frequecy dependent optical properties in the linear optical range are also investigated.

KEYWORDS:

• Pnictogens
• band structures
• interband transitions

PACS:

• 42.70.-a
• 74.25.Gz
• 82.20.Wt

Acknowledgements

This research project was supported by a grant from the “Research Center of Female Scientific and Medical Colleges,” Deanship of Scientific Research, King Saud University.

Disclosure statement

No potential conflict of interest was reported by the authors.