Comparison of first principles and semi-empirical models of the structural and electronic properties of Ge1−xSnx alloys
dc.contributor.author | O'Halloran, Edmond J. | |
dc.contributor.author | Broderick, Christopher A. | |
dc.contributor.author | Tanner, Daniel S. P. | |
dc.contributor.author | Schulz, Stefan | |
dc.contributor.author | O'Reilly, Eoin P. | |
dc.contributor.funder | Science Foundation Ireland | en |
dc.contributor.funder | National University of Ireland | en |
dc.contributor.funder | Higher Education Authority | en |
dc.contributor.funder | Department of Education and Skills | en |
dc.contributor.funder | Department of Jobs, Enterprise and Innovation | en |
dc.date.accessioned | 2019-11-18T10:08:33Z | |
dc.date.available | 2019-11-18T10:08:33Z | |
dc.date.issued | 2019-09-14 | |
dc.date.updated | 2019-11-18T09:46:23Z | |
dc.description.abstract | We present and compare three distinct atomistic models—based on first principles and semi-empirical approaches—of the structural and electronic properties of Ge1−xSnx alloys. Density functional theory calculations incorporating Heyd–Scuseria–Ernzerhof (HSE), local density approximation (LDA) and modified Becke–Johnson (mBJ) exchange-correlation functionals are used to perform structural relaxation and electronic structure calculations for a series of Ge1−xSnx alloy supercells. Based on HSE calculations, a semi-empirical valence force field (VFF) potential and sp3s∗ tight-binding (TB) Hamiltonian are parametrised. Comparing the HSE, LDA+mBJ and VFF+TB models, and using the HSE results as a benchmark, we demonstrate that: (1) LDA+mBJ calculations provide an accurate first principles description of the electronic structure at reduced computational cost, (2) the VFF potential is sufficiently accurate to circumvent the requirement to perform first principles structural relaxation, and (3) VFF+TB calculations provide a good quantitative description of the alloy electronic structure in the vicinity of the band edges. Our results also emphasise the importance of Sn-induced band mixing in determining the nature of the conduction band structure of Ge1−xSnx alloys. The theoretical models and benchmark calculations we present inform and enable predictive, computationally efficient and scalable atomistic calculations for disordered alloys and nanostructures. This provides a suitable platform to underpin further theoretical investigations of the properties of this emerging semiconductor alloy. | en |
dc.description.sponsorship | National University of Ireland (Post-Doctoral Fellowship in the Sciences) | en |
dc.description.status | Peer reviewed | en |
dc.description.version | Accepted Version | en |
dc.format.mimetype | application/pdf | en |
dc.identifier.articleid | 314 | en |
dc.identifier.citation | O'Halloran, E. J., Broderick, C. A., Tanner, D. S. P., Schulz, S. and O'Reilly, E. P. (2019) 'Comparison of first principles and semi-empirical models of the structural and electronic properties of Ge1−xSnx alloys', Optical and Quantum Electronics, 51(9), 314 (23pp). doi: 10.1007/s11082-019-1992-8 | en |
dc.identifier.doi | 10.1007/s11082-019-1992-8 | en |
dc.identifier.eissn | 1572-817X | |
dc.identifier.endpage | 23 | en |
dc.identifier.issn | 0306-8919 | |
dc.identifier.issued | 9 | en |
dc.identifier.journaltitle | Optical and Quantum Electronics | en |
dc.identifier.startpage | 1 | en |
dc.identifier.uri | https://hdl.handle.net/10468/9020 | |
dc.identifier.volume | 51 | en |
dc.language.iso | en | en |
dc.publisher | Springer Nature Switzerland AG | en |
dc.relation.project | info:eu-repo/grantAgreement/SFI/SFI Investigator Programme/15/IA/3082/IE/Multiscale Simulation and Analysis of emerging Group IV and III-V Semiconductor Materials and Devices/ | en |
dc.relation.project | info:eu-repo/grantAgreement/SFI/SFI Investigator Programme/14/IA/2513/IE/Silicon Compatible, Direct Band-Gap Nanowire Materials For Beyond-CMOS Devices/ | en |
dc.relation.project | info:eu-repo/grantAgreement/SFI/SFI Starting Investigator Research Grant (SIRG)/13/SIRG/2210/IE/Shaping the electronic and optical properties of non- and semi-polar nitride-based semiconductor nanostructures/ | en |
dc.relation.uri | https://link.springer.com/journal/11082/topicalCollection/AC_9b884ebf2958f06cb3bcc6ef01bec32a | |
dc.rights | © 2019, Springer Science+Business Media, LLC, part of Springer Nature. This is a post-peer-review, pre-copyedit version of an article published in Optical and Quantum Electronics. The final authenticated version is available online at: https://doi.org/10.1007/s11082-019-1992-8 | en |
dc.subject | Group-IV semiconductors | en |
dc.subject | Electronic structure | en |
dc.subject | Density functional theory | en |
dc.subject | GeSn alloys | en |
dc.subject | Tight binding | en |
dc.title | Comparison of first principles and semi-empirical models of the structural and electronic properties of Ge1−xSnx alloys | en |
dc.type | Article (peer-reviewed) | en |