Dynamic Phenomena of Magnetic Materials

Olle Eriksson
Olle Eriksson. Photo:Mikael Wallerstedt.

The Knut and Alice Wallenberg Foundation granted in 2018 in total 640 million SEK in project grants for 2018 to 22 research projects which where assessed to hold the highest international standards and have the opportunity to lead to future scientific breakthroughs. The Department of Physics and Astronomy was main applicant in two and fellow applicant in one of these projects that was granted in total 78.5 million SEK during five years.

Project Description

Main applicant: Olle Eriksson, Division of Materials Theory
Project title: Dynamic Phenomena of Magnetic Materials
Grant amount: 22 200 000 SEK during five years
Funder: Project grant from the Knut and Alice Wallenberg Foundation

Magnetic materials have played a central role for the societal development throughout the human history. These materials constitute a cornerstone for the information-based society today. The amount of stored information is doubled every eighteenth month and a vast majority of this is stored in magnetic devices. To meet the need for an increasing storage capacity and faster information processing, existing techniques must be improved and new technologies must be developed.

In this KAW project, we will use state of the art theoretical methods to address fundamental issues regarding the dynamics of magnetic materials, and to investigate how subtle magnetic phenomena can be used for future information technologies.

Magnetic materials can show collective, but particle-like magnetic vortices called ‘skyrmions’ and ‘merons’. These whirling structures have topological features that lead to high stability to perturbations, but, at the same time, are easy to manipulate by means of electrical currents. Therefore, skyrmions are strong candidates for data storage applications. We will combine our computational methods with machine learning techniques in order to search for magnetic materials that are optimal for harbouring skyrmion and meron states. In particular, we will investigate meron-based implementations of time crystals, systems that behave periodically in time even in absence of a periodic driving force. Time crystals as well as purely quantum-mechanical effects can be used for applications such as atomic clocks, but also for communication protocols and efficient quantum computers. A central aspect for these applications is the ability to create and manipulate many-body entangled quantum states. We will examine entanglement among magnons, which are collective excitations of magnets, in order to develop a new hardware for quantum computation and communication.

An important part of the project is also to develop quantum-mechanical computational and simulation methods designed for magnetic materials. These methods will include crystal vibrations in the simulation of the magnetic properties. The fundamental relation between the structure of the material and its magnetic response at a femtosecond time scale will be examined by means of our new methods.