Abstract
Femtosecond laser pulse excitation of multi-sub-lattice rare-earth (RE) transition-metal (TM) ferrimagnets opens the way to trigger ultrafast precessional switching and moreover all-optical magnetization switching (AOS). This AOS phenomena originated from sub-lattice nature is fundamentally different from conventional magnetic field driven switching mechanism. In this study, we show that the AOS efficiently works even near compensation composition ratio Ccomp or compensation temperature Tcomp that makes hardness to magnetic field driven net-magnetization (Mnet) reversal. Under the various conditions of Mnet, all optically created domain sizes were almost determined by only the condition of laser excitation. Furthermore, we suggested that the switching domain area can be estimated by a fluence threshold Wft.
