Tailoring of Polar Topologies with Optical Pulses

The past decade has witnessed dramatic progress related to the emergence of different topological polar textures in oxide nanostructures such as vortices, skyrmions, merons, hopfions, among others.

These exotic phases are opening new technological perspectives due to their exotic functional properties like negative capacitance, chirality or ultrafast dynamical response.

In addition, the fact that these states are metastable and thus non-volatile, allows to consider them as multiweights, that one can exploit in artificial neuromorphic synapses.

The main goal of the collaboration between the researcher and the host group is to perform first-principles based effective atomic potential simulations (retrieving all the structural degrees of freedom) of topological phases interacting with electric pulses from a truly quantum-mechanical point of view to tailor the resulting polar ordering.

A key novelty of this proposal and the ambitious objective that it pursues, is to study and characterize, from a fundamental point of view, the phonon modes active in the different topological orderings to figure out the relevant modes to be excited and be able to design concrete pulses that provide a deterministic control of the resulting effect on the polar ordering of the material.

Other current approaches to the problem only rely on the coupling between two or three modes with their interactions fitted from DFT. Therefore, a full atomistic view of the problem would be desired.

Due to the promising technologically relevant results on the near horizon, a deeper and more advanced theoretical inspection without the omission of atomic degrees of freedom that might be relevant for the description of the material is needed with urgency. This project directly tackles these needs.

Although being a theoretical work collaboration with leading experimental groups at UCL and UNIGE will be pursued in order to validate the theoretical model and increase the technology readiness level of the project