Helicity-dependent all-optical switching in hybrid metal-ferromagnet structures for ultrafast magnetic data storage

• Online Access: http://hdl.handle.net/2047/D20236914

The emerging Big Data era demands the rapidly increasing need for speed and capacity of storing and processing information. Standalone magnetic recording devices, such as hard disk drives (HDDs), have always been playing a central role in modern data storage and continuously advancing. Recognizing the growing capacity gap between the demand and production, industry has pushed the bit areal density in HDDs to 900 Giga-bit/square-inch, a remarkable 450-million-fold increase since the invention of the first hard disk drive in 1956. However, the further development of HDD capacity is facing a pressing challenge, the so-called superparamagnetic effect, that leads to the loss of information when a single bit becomes too small to preserve the magnetization[1, 2]. This requires new magnetic recording technologies that can write more stable magnetic bits into hard magnetic materials.