Scaling of all-optical switching to nanometer dimensions

Switching the magnetization of nanoscale magnetic dots is one of the most crucial processes for use in electronics applications such as MRAM and logic. The unique ability to switch magnetization entirely optically has been shown possible in a limited selection of materials often using either circularly polarized or linearly polarized light. The material GdFeCo, however, is rare in that it can be switched all-optically without the need for a particular polarization of light, and for which the switching occurs on ultrafast, picosecond timescales. This work explores the potential for use of GdFeCo in nanoscale ultrafast magnetic devices. To do so, we first fabricate nanoscale dots of the magnetic material, and then we experimentally determine its all-optical switching (AOS) properties down to nanometer dot dimensions.