Veronika Lamparská

Project Description

This PhD project focuses on discovering new materials that can efficiently convert charge currents into spin signals, an essential functionality for next-generation, energy-efficient electronic devices operating without magnetic fields. Our recent work has shown that chiral crystals, whose structure lacks mirror and inversion symmetries, can perform this conversion far better than conventional materials. For example, in chiral tellurium we demonstrated an exceptional conversion efficiency of around 50% and unusually long spin relaxation times, enabled by strong polarization of the total angular momentum. The goal of this project is to find and understand new chiral materials that outperform Te, ideally with even higher efficiency and spin diffusion lengths reaching the micrometre scale, and consisting of lighter elements. The PhD candidate will contribute to this effort through three main directions:

Theoretical modelling: developing and applying methods to understand how spin and orbital angular momentum are generated and how they relax in chiral crystals. In some materials, orbital contributions are much larger than spin contributions; understanding and quantifying this behaviour is an important scientific challenge.

Symmetry analysis: using group-theoretical tools to identify which crystal symmetries can host persistent spin or orbital textures that protect the generated angular momentum and allow long-distance spin and orbital transport. This includes understanding the effects of reduced dimensionality at the nanoscale.

High-throughput materials discovery: performing automated ab initio calculations using Quantum Espresso and tight-binding Hamiltonians from PAOFLOW to screen a large number of chiral candidates. These simulations will account for realistic disorder effects (in collaboration with INL) and will identify promising materials for future devices.

Host institution

Rijksuniversiteit Groningen is a Top 100 (#69 in ARWU Shanghai Ranking 2024 and #79 in the World University Rankings 2024) research university where inter- and cross-disciplinary research leads to scientific breakthroughs and societal innovation and in which talented students are trained as innovators who will contribute to a sustainable society.

The Computational Materials Science group performs theoretical research focused on the design of novel materials and devices, whose functionalities emerge from the rich physics of spin-orbit interaction. In order to simulate structural, electronic, magnetic and transport properties of materials, Dr. Sławińska’s group uses computational approaches based on density functional theory complemented by tight-binding PAO Hamiltonians, Green’s functions methods and symmetry analysis. Current studies explore surfaces, thin films and hybrid structures, such as interfaces or van der Waals heterostructures, hosting quantum or topological phases that can be controlled by external stimuli.