Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2409.15673 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866912606654038016 |
|---|---|
| author | Ghosh, Andreas Schankler, Aaron M. Rappe, Andrew M. |
| author_facet | Ghosh, Andreas Schankler, Aaron M. Rappe, Andrew M. |
| contents | Tight-binding models provide great insight and are a low-cost alternative to \emph{ab initio} methods for calculation of a material's electronic structure. These models are used to calculate optical responses, including nonlinear optical effects such as the shift current bulk photovoltaic effect. The validity of tight-binding models is often evaluated by comparing their band structures to those calculated with Density Functional Theory. However, we find that band structure agreement is a necessary but not sufficient condition for accurate optical response calculations. In this Letter, we compute the shift current response and dielectric tensor using a variety of tight-binding models of {MoS$_2$}, including both Slater-Koster and Wannier tight-binding models that treat the Mo $4d$ orbitals and/or S $3p$ orbitals. We also truncate hoppings in the Wannier function models to next-nearest neighbor, as is common in tight-binding methods, in order to gauge the effect on optical response. By examining discrepancies in energies and optical matrix elements, we determine the interpolation quality of the different tight-binding models and establish that agreement in both band structure and wavefunctions is required to accurately model optical response, |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2409_15673 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Choosing Tight-Binding Models for Accurate Optoelectronic Responses Ghosh, Andreas Schankler, Aaron M. Rappe, Andrew M. Materials Science Tight-binding models provide great insight and are a low-cost alternative to \emph{ab initio} methods for calculation of a material's electronic structure. These models are used to calculate optical responses, including nonlinear optical effects such as the shift current bulk photovoltaic effect. The validity of tight-binding models is often evaluated by comparing their band structures to those calculated with Density Functional Theory. However, we find that band structure agreement is a necessary but not sufficient condition for accurate optical response calculations. In this Letter, we compute the shift current response and dielectric tensor using a variety of tight-binding models of {MoS$_2$}, including both Slater-Koster and Wannier tight-binding models that treat the Mo $4d$ orbitals and/or S $3p$ orbitals. We also truncate hoppings in the Wannier function models to next-nearest neighbor, as is common in tight-binding methods, in order to gauge the effect on optical response. By examining discrepancies in energies and optical matrix elements, we determine the interpolation quality of the different tight-binding models and establish that agreement in both band structure and wavefunctions is required to accurately model optical response, |
| title | Choosing Tight-Binding Models for Accurate Optoelectronic Responses |
| topic | Materials Science |
| url | https://arxiv.org/abs/2409.15673 |