Optical spectrum and excitons in bulk and monolayer MX2 (M=Zr, Hf; X=S, Se). Issue 4 (4th December 2015)

• Record Type: Journal Article
• Authors: Abdulsalam, Mahmud; Joubert, Daniel P.
• Is Part Of: Physica status solidi. Volume 253:Issue 4(2016)
• Page Start: 705
• Page End: 711
• Publication Date: 2015-12-04
• Subjects: Bethe–Salpeter approximation -- Excitons -- GW approximation -- optical spectra -- transition metal chalcogenides; Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201552584
• Languages: English
• ISSNs: 0370-1972

Abstract

Abstract: Abstractauthoren We present first principles calculations of the electronic and optical properties of bulk and monolayer structures for four transition metal chalcogenides, MX 2 ( M = Zr and Hf; X = S, Se), using a post density functional many‐body perturbation GW approximation in conjunction with the Bethe–Selpeter approximation (GW‐BSE). Optical absorption spectra predict the presence of a strongly bound exciton that lies below the direct band gap in two bulk (HfS 2 and ZrSe 2 ) and in all the monolayer structures. The binding energy of the excitons are predicted to lie between 0.11 and 0.96 eV.