Spin-polaronics, an emerging technology

TL;DR

This paper theoretically investigates the properties of spin-polarons in La-doped CaMnO3 using first-principles derived Hamiltonians, revealing controllable mobility and potential for atomic-scale information storage, highlighting spin-polaronics as an emerging nanotech field.

Contribution

It introduces a parameter-free, first-principles-based Hamiltonian for spin-polarons in CaMnO3 and explores their stability, mobility, and technological applications through advanced simulations.

Findings

Excellent agreement with experimental data and previous theories.

Control over spin-polaron mobility via temperature and electric field.

Feasibility of writing and erasing atomic-scale information using spin-polarons.

Abstract

The static and dynamic properties of spin-polarons in La-doped $CaMnO_3$ are explored theoretically, by means of an effective low energy Hamiltonian. All parameters from the Hamiltoniain are evaluated from first principles theory, without adjustable parameters. %We compare different geometries, like spin-polarons in bulk, surface and as single two-dimensional layers. The Hamiltonian is used to investigate the temperature stability as well as the response to an external applied electric field, for spin-polarons in bulk, surface and as single two-dimensional layers. Technically this involves atomistic spin-dynamics simulations in combination with kinetic Monte Carlo simulations. Where a comparison can be made, our simulations exhibit an excellent agreement with available experimental data and previous theory. Remarkably, we find that excellent control of the mobility of spin-polarons in this material can be achieved, and that the critical parameters deciding this is the temperature and strength of the applied electrical field. We outline different technological implications of spin-polarons, and point to spin-polaronics as an emerging sub-field of nano-technology. In particular, we demonstrate that it is feasible to write and erase information on atomic scale, by use of spin-polarons in $CaMnO_3$.