Supervisor: Irene Aguilera. Combining nontrivial band topology with magnetic order can lead to the emergence of exotic phenomena such as the Quantum Anomalous Hall Effect (QAHE). In Amsterdam, extensive experimental and theoretical research is ongoing to design the optimal candidate for QAHE that is stable up to technologically relevant temperatures. The efforts concentrate on the family of MnSb2Te4.
PROJECT 1. Electron-magnon interactions in magnetic topological insulator MnSb2Te4: Recently, our experimental colleagues at Mark Golden’s group have observed a band anomaly in the band structure of MnSb2Te4 that we speculate could be the result of electron-magnon scattering. In this project, you will calculate the electronic spectral function of MnSb2Te4 in the presence and absence of magnons to elucidate the role of electron-magnon interactions in its electronic structure. The theoretical spectral functions will then be compared to the already available spectral functions obtained by angle-resolved photoemission spectroscopy at Mark’s group.
PROJECT 2. First-principles calculations of structural and electronic properties of MSb2Te4 (M=V, Cr, Mn, Fe): In this project, we want to investigate the effect of replacing Mn by other transition metals such as V, Cr, and Fe. You will calculate the modification of the lattice parameters upon replacement of Mn by other transition metals and the electronic spectral functions (band structures) of the resulting compounds.
These works run in collaboration with the experimental groups of Anna Isaeva (growth) and Mark Golden (ARPES). You will use methods based on many-body perturbation theory (MBPT) that are currently implemented in the first-principles code SPEX. These projects are for you if you have a solid background in electromagnetism, and quantum mechanics, and you are interested in numerical simulations and properties of matter.
Literature:
Magnetic topological insulators.
(For project 1) Electron-magnon scattering in elementary ferromagnets from first principles.