Dynamical control of topology in ferroelectric skyrmions via twisted light

TL;DR

This paper demonstrates how twisted light can dynamically generate and control topological skyrmions in ferroelectric ultrathin films, revealing a new method for manipulating topological states via light-matter interactions.

Contribution

It introduces a first-principles-based simulation approach showing twisted light can create and manipulate ferroelectric skyrmions and transfer topological winding numbers.

Findings

Twisted light excites and drives dynamical polar skyrmions.

Skyrmions are created and annihilated at film interfaces.

Skyrmion character transitions between Bloch and Neel types.

Abstract

Twisted light carries a non-zero orbital angular momentum, that can be transferred from light to electrons and particles ranging from nanometers to micrometers. Up to now, the interplay between twisted light with dipolar systems has scarcely been explored, though the latter bear abundant forms of topologies such as skyrmions and embrace strong light-matter coupling. Here, using first-principles-based simulations, we show that twisted light can excite and drive dynamical polar skyrmions and transfer its nonzero winding number to ferroelectric ultrathin films. The skyrmion is successively created and annihilated alternately at the two interfaces, and experiences a periodic transition from a markedly "Bloch" to "Neel" character, accompanied with the emergence of a "Bloch point" topological defect with vanishing polarization. The dynamical evolution of skyrmions is connected to a constant jump of topological number between "0" and "1" over time. These intriguing phenomena are found to have an electrostatic origin. Our study thus demonstrates that, and explains why, this unique light-matter interaction can be very powerful in creating and manipulating topological solitons in functional materials.