All-optical switching in Cr- and Mn-doped L⁢1₀ Fe⁢Pt thin films

Abstract

Optical manipulation of the magnetization of thin films opens up exciting possibilities for ever-faster magnetic storage applications. In this context, L⁢10 chemically ordered Fe⁢Pt thin films are of particular interest due to their high perpendicular magnetic anisotropy and their use as a storage material for heat-assisted magnetic recording devices. However, these materials are difficult to manipulate with external fields due to their high coercivity field. Thus, we want to explore the possibility of tailoring the properties of these materials to enable switching using all-optical techniques. While stochastic all-optical switching between partially magnetized states has been reported for undoped Fe⁢Pt thin films, we have investigated to what extent doping with third elements can influence the switching behavior. Reducing the saturation magnetization may be one way to facilitate all-optical switching. While this is expected with the introduction of additional elements, we also want to highlight the role of the inverse Faraday effect and the magnetic circular dichroism in stochastic all-optical switching. In this study, Cr was found to be a promising dopant, which can almost double the relative magnetization change of the partially magnetized states compared to pure Fe⁢Pt.