ATMOST stands for Atomistic theory and simulations for THz spintronic devices. Supported by Science Foundation Ireland (SFI) under the Starting Investigator Research Grant (SIRG) programme, ATMOST is to start in April 2020 and aims to develop predictive computer models to advance the design of novel spintronic devices of great technological value – spintronic THz oscillators. The THz range of the electromagnetic spectrum (high-frequency microwaves) is the domain of important chemical and biological processes. Importantly, the THz range is expected to host the short-range, high-bandwidth telecommunications of the future.
We have gained experience in modelling STT in magnetic tunnel junctions (MTJ) (see below) from first principles and using that in a multi-scale theory with classical atomistic spin dynamics (ASD) scheme to model STT-driven switching of conventional (ferromagnet-based) MTJs. Together with providing a tool for writing in magnetic memory applications, STT can also excite and sustain magnetisation precession accompanied by electromagnetic radiation. Characteristic rates of oscillation of the compensating atomic-scale magnetic moments in AFMs are in the THz range which makes them a great candidate for novel THz sources. e.g. the following conceptual spintronic oscillator:
In ATMOST we have set out to develop a multiscale theory for modelling and optimising THz spintronic oscillators based on novel ferri-magnetic MTJs, for instance, something like this:
Moving onto low-moment materials, however, will constitute a non-trivial generalisation of our mapping scheme between the two levels of atomistic theory. Together with the ab initio STT, we will introduce position-dependent magnetic parameters for the ASD simulations. Furthermore, extensions of the scheme will be introduced in order to take into account temperature and heat gradients, and possibly additional microscopic excitations. We believe that, extended as such, such multi-scale modelling scheme will be unique in terms of accuracy and efficiency and it would have the potential of becoming an essential tool in the design and optimisation of novel spintronic devices.
*** Open PhD position on ATMOST *** Please contact for details.
