SciPost Submission Page
calcQPI: A versatile tool to simulate quasiparticle interference
by Peter Wahl, Luke C. Rhodes, Carolina A. Marques
Submission summary
| Authors (as registered SciPost users): | Luke C. Rhodes · Peter Wahl |
| Submission information | |
|---|---|
| Preprint Link: | https://arxiv.org/abs/2507.22137v2 (pdf) |
| Code repository: | https://github.com/gpwahl/calcqpi-release |
| Code version: | v1 |
| Code license: | GPL-3.0 |
| Data repository: | https://github.com/gpwahl/calcqpi-examples |
| Date accepted: | Oct. 15, 2025 |
| Date submitted: | Sept. 23, 2025, 8:52 a.m. |
| Submitted by: | Peter Wahl |
| Submitted to: | SciPost Physics Codebases |
| Ontological classification | |
|---|---|
| Academic field: | Physics |
| Specialties: |
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| Approaches: | Theoretical, Computational |
Abstract
Quasiparticle interference imaging (QPI) provides a route to characterize electronic structure from real space images acquired using scanning tunneling microscopy. It emerges due to scattering of electrons at defects in the material. The QPI patterns encode details of the $k$-space electronic structure and its spin and orbital texture. Recovering this information from a measurement of QPI is non-trivial, requiring modelling not only of the dominant scattering vectors, but also the overlap of the wave functions with the tip of the microscope. While, in principle, it is possible to model QPI from density functional theory (DFT) calculations, for many quantum materials it is more desirable to model the QPI from a tight-binding model, where inaccuracies of the DFT calculation can be corrected. Here, we introduce an efficient code to simulate quasiparticle interference from tight-binding models using the continuum Green's function method.
List of changes
• We have updated the model and figure for the Rashba-spin-orbit split system, because due to a typo the Hamiltonian in the examples was non-hermitian. The results look identical.
• We have fixed minor bugs in the code which came up while the review process was going on. These only affect the interface, but none of the core components.
Published as SciPost Phys. Codebases 61-r1.0 (2025) , SciPost Phys. Codebases 61 (2025)
Reports on this Submission
Report #1 by Andreas Kreisel (Referee 1) on 2025-10-4 (Invited Report)
- Cite as: Andreas Kreisel, Report on arXiv:2507.22137v2, delivered 2025-10-04, doi: 10.21468/SciPost.Report.12065
Report
The authors have incorporated changes to the manuscript according to the comments of both referees such that minor mistakes, typos or imprecise statements are removed. The addition of the procedure for obtaining ab-initio Wannier functions is certainly valuable and rounds up the presentation of the calcQPI code.
Looking into the changes in detail, I found a few small issues that could be fixed:
1) Figure 8 has been updated (single impurity vs. double impurity calculation). In the caption it is written “(b) Bulk (left half) and surface (right half) spectral function of the model”. Seems that in the new figure, bulk and surface parts are overlayed and plotted in “red” and “black” shading. Minimally, the caption has to be changed; better would be actually the splitting of the figure in two halves with plotting bulk and surface spectral function as it was in the previous version.
2) Figure 2; the equation in the box seems still not to be identical to Eq. (7). G_0 does only have one spatial index and the second Green function should have argument “ -R’ ”.
Recommendation
Publish (surpasses expectations and criteria for this Journal; among top 10%)