Band gap temperature-dependence and exciton-like state in copper antimony sulphide, CuSbS2

Birkett, Max ORCID: 0000-0002-6076-6820, Savory, Christopher N, Rajpalke, Mohana K, Linhart, Wojciech M, Whittles, Thomas J, Gibbon, James T ORCID: 0000-0003-1548-0791, Welch, Adam W, Mitrovic, I ORCID: 0000-0003-4816-8905, Zakutayev, Andriy, Scanlon, David O
et al (show 1 more authors) (2018) Band gap temperature-dependence and exciton-like state in copper antimony sulphide, CuSbS2. APL Materials, 6 (8). 084904-084904.

This is the latest version of this item.

[img] Text
author_accepted_manuscript.pdf - Author Accepted Manuscript

Download (1MB)
[img] Text
author_accepted_supplementary_material.pdf - Author Accepted Manuscript

Download (4MB)
[img] Text
BirkettAPLMat6(2018)084904.pdf - Published version

Download (784kB)


The temperature-dependence of the band gap of the proposed photovoltaic absorber copper antimony sulphide (CuSbS2) has been studied by Fourier-transform infrared spectroscopy. The direct gap rises from 1.608 to 1.694 eV between 300 and 4.2 K. Below 200 K an exciton-like feature develops above the absorption edge at 1.82 eV. First-principles calculations evaluate band structure, band symmetries, and dipole selection rules, suggesting distinctly enhanced absorption for certain excitonic optical transitions. Striking consistency is seen between predicted dielectric and absorption spectra and those determined by ellipsometry, which reveal rapidly strengthening absorption passing 105 cm−1 at 2.2 eV. These results suggest beneficial photovoltaic performance due to strong optical absorption arising from unusually strong electron–hole interactions in polycrystalline CuSbS2 material.

Item Type: Article
Depositing User: Symplectic Admin
Date Deposited: 11 Jun 2018 06:28
Last Modified: 08 Aug 2023 00:30
DOI: 10.1063/1.5030207
Related URLs:

Available Versions of this Item