Research Seminar in Mathematics - An introduction to ab-initio magnetization dynamics

Speaker

Danny Thonig, Örebro University.

Abstract

The time-integrated amount of stored information is doubled roughly every eighteen months, and since the majority of the world’s information is stored in magnetic media, the possibility to write and retrieve information in a magnetic material at ever greater speed, bigger data transmission rates and with lower energy consumption, has obvious benefits for our society. Hence the seemingly simple switching of a magnetic unit, a magnetic bit, is a crucial process which defines how efficiently information can be stored and retrieved from a magnetic memory. From an application point of view, it is apparent that it is advantageous to be able to switch the magnetization of a bit as fast as possible while minimizing energy losses. It implies also to understand the microscopic origin of the magnetization dynamics in magnetic materials.

Within my talk I will give a general introduction about what magnetism is, from where it originates, and how it can be treated in modeling. Why magnetism is materials specific and - although known as rather static - magnetism is dynamic will be motived after the introduction part. Here, the equation of motion will be discussed more in detail and applied to certain questions that occurred from experimental observations. All this is implemented in the software package "Cahmd" (https://cahmd.gitlab.io/cahmdweb/), which was developed by the PI. I will finish my presentation with an outlook on future challenges.