17.3.2021
Juraj Krempaský (Paul Scherrer Institute, Switzerland): 
The simplest ferroelectric system with non-trivial topology is paving the way towards antiferromagnetic spintronics 

Abstrakt:

In the past few years, we observe renewed interest and development of materials
with promising new breakthroughs in areas like superconductivity, spintronics
and quantum computing. Of special interest are materials that possess functional
properties that change material physical properties upon external fields, for
example in ferroelectric or multiferroic systems. My presentation focus on
simplest binary ferroelectric GeTe that serve as a model system for bottom‑up
study of all these phenomena. GeTe exhibits an intriguing multiple non‑trivial
topology in its electronic band structure due to the existence of triple-point
and type-II Weyl fermions. These recent findings go well beyond the previously
reported giant Rashba spin splitting which we managed to control by external
fields. Finally, upon Mn-doping the material bears interesting ferrimagnetic
properties, paving way to achieve a role for topological materials in
spintronics.