Chirality in the Magnetotransport Properties of Tellurium, and How to Obtain High-Quality Wannier Functions Using Topological Quantum Chemistry

Elemental tellurium is a prototypical material for studying chiral properties, owing to its simple structure of atomic spirals along the c-axis. However, there remain unresolved questions about its behavior. In the first part of my talk, I will discuss our recent results [1] on the evaluation of electrical magnetochiral anisotropy (EMChA) in trigonal tellurium, based on Berry-Boltzmann equations and Wannier interpolation, and how they compare with experimental data. We find that different experimental techniques yield opposite signs for the effect (our theory agrees with some of them), and a possible reason for this discrepancy is the lack of consensus on how to experimentally distinguish between the left- and right-handed enantiomers.

In the second part of my talk, I will present my recent developments in constructing Wannier functions using the WannierBeri code, as part of my efforts to challenge the dominance of Wannier90. Specifically, I have implemented the construction of symmetry-adapted Wannier functions with spin-orbit coupling, a frozen window, and compatibility with multiple DFT codes (VASP, Quantum Espresso, Abinit, etc.), thereby addressing limitations of the Wannier90 implementation. Additionally, I propose a method for selecting initial projections based on the symmetry indicators of DFT Bloch bands. This method allows the identification of initial projections that are compatible with all irreducible representations of the bands within the frozen window, requiring minimal manual inspection. As a result, this approach has the potential to be automated for high-throughput calculations.  [1] Electrical magnetochiral anisotropy in trigonal tellurium from first principles. Xiaoxiong Liu, Ivo Souza, Stepan S. Tsirkin, https://arxiv.org/abs/2303.10164
[2] Current-induced magnetization caused by crystal chirality in nonmagnetic elemental tellurium. Tetsuya Furukawa, Yuta Watanabe, Naoki Ogasawara, Kaya Kobayashi, and Tetsuaki Itou, Phys. Rev. Research 3, 023111 (2021)
[3] Symmetry-adapted Wannier functions in the maximal localization procedure. R. Sakuma, Phys. Rev. B 87, 235109 (2013)