Ellipsometric characterization and density-functional theory analysis of anisotropic optical properties of single-crystal α-SnS

Journal Article · Mon Jul 07 04:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4886915· OSTI ID:22306163

Banai, R. E.; Brownson, J. R. S. ^[1]; Burton, L. A.; Walsh, A. ^[2]; To, B. ^[3]; Hofherr, F.; Sorgenfrei, T.; Cröll, A. ^[4]

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1. Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
2. Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)
3. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
4. Crystallography—Institute of Earth and Environmental Sciences, University of Freiburg, 79104 Freiburg (Germany)

We report on the anisotropic optical properties of single-crystal tin monosulfide (SnS). The components ε{sub a}, ε{sub b}, and ε{sub c} of the pseudodielectric-function tensor (ε)=(ε₁)+i(ε₂) spectra are taken from 0.73 to 6.45 eV by spectroscopic ellipsometry. The measured (ε) spectra are in a good agreement with the results of the calculated dielectric response from hybrid density functional theory. The (ε) spectra show the direct band-gap onset and a total of eight above-band-gap optical structures that are associated with the interband-transition critical points (CPs). We obtain accurate CP energies by fitting analytic CP expressions to second-energy-derivatives of the (ε) data. Their probable electronic origins and implications for photovoltaic applications are discussed.

• OSTI ID: 22306163
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 1 Vol. 116; ISSN JAPIAU; ISSN 0021-8979
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
DENSITY FUNCTIONAL METHOD
DIELECTRIC MATERIALS
ELLIPSOMETRY
ENERGY-LEVEL TRANSITIONS
EV RANGE
MONOCRYSTALS
OPTICAL PROPERTIES
PHOTOVOLTAIC EFFECT
SPECTRA
TIN SULFIDES