Ab initio calculations of the concentration dependent band gap reduction in dilute nitrides
| Autor: | Eric W. Fischer, Phil Rosenow, Lars C. Bannow, Stephan W. Koch, Kerstin Volz, Ralf Tonner, Wolfgang Stolz |
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| Rok vydání: | 2017 |
| Předmět: |
Condensed Matter - Materials Science
Condensed matter physics Chemistry Band gap Ab initio Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences 02 engineering and technology Electronic structure Nitride 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics Condensed Matter::Materials Science Ab initio quantum chemistry methods Distortion 0103 physical sciences Atom Density functional theory 010306 general physics 0210 nano-technology |
| DOI: | 10.48550/arxiv.1705.10763 |
| Popis: | While being of persistent interest for the integration of lattice-matched laser devices with silicon circuits, the electronic structure of dilute nitride III/V-semiconductors has presented a challenge to ab initio computational approaches. The root of this lies in the strong distortion N atoms exert on most host materials. Here, we resolve these issues by combining density functional theory calculations based on the meta-GGA functional presented by Tran and Blaha (TB09) with a supercell approach for the dilute nitride Ga(NAs). Exploring the requirements posed to supercells, we show that the distortion field of a single N atom must be allowed to decrease so far, that it does not overlap with its periodic images. This also prevents spurious electronic interactions between translational symmetric atoms, allowing to compute band gaps in very good agreement with experimentally derived reference values. These results open up the field of dilute nitride compound semiconductors to predictive ab initio calculations. Comment: 17 pages, 4 figures |
| Databáze: | OpenAIRE |
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