Optoelectronic properties of three PbSe polymorphs
| Autor: | Faheem K. Butt, S. AlFaify, Zulfiqar Ali Shah, Amel Laref, Bakhtiar Ul Haq, Aijaz Rasool Chaudhry, R. Ahmed, Ahmed S. Jbara |
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| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Materials science Band gap business.industry Process Chemistry and Technology Exciton Binding energy 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials 0103 physical sciences Materials Chemistry Ceramics and Composites Optoelectronics Orthorhombic crystal system Direct and indirect band gaps Density functional theory 0210 nano-technology Ground state business Plasmon |
| Zdroj: | Ceramics International. 46:22181-22188 |
| ISSN: | 0272-8842 |
| DOI: | 10.1016/j.ceramint.2020.05.295 |
| Popis: | The narrow bandgap PbSe has attracted a remarkable interest from the researchers in recent years for their potential optoelectronics and photovoltaic applications. In this article, we report the optoelectronic properties of cubic (NaCl-type) and orthorhombic (Cmcm- and Pnma-type) polymorphs of PbSe using the density functional theory based first-principles approaches. In accordance with the available literature, the NaCl–PbSe has been found stable in the ground state, whereas the Cmcm-, Pnma-types of PbSe have been realized at intermediate pressure of ~4.5 GPa. The electronic structures and optical spectra of these polymorphs have been determined using the Tran-Blaha modified Becke-Johnson exchange potential with and without spin-orbit coupling (SOC) effects. The inclusion of SOC has shown important effects on the electronic structures and consequently on the optical spectra. Despite SOC driven energy gap narrowing of these polymorphs, the direct bandgap nature of Cmcm-PbSe calculated with TB-mBJ has changed to indirect nature with the inclusion of SOC. Moreover, our results of the optical spectra of NaCl–PbSe have shown that this phase is isotropic, whereas a sufficiently high degree of anisotropy in the optical spectra has been recorded for Cmcm-, Pnma-types of PbSe. These PbSe polymorphs exhibited a high optical absorption that approaches as large as 106 cm−1. Moreover, our study provides comprehensive details of exciton binding energies and plasmon energies. This work is believed to provide a strong foundation to exploit the optoelectronic character of the studied phases of PbSe for next-generation optoelectronic and photovoltaic applications. |
| Databáze: | OpenAIRE |
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