SNR improvements for advanced longitudinal recording media

Schemes for SNR enhancement for advanced longitudinal recording media are discussed. SNR improvement is obtained by utilizing a bi-magnetic layer media, where the initial magnetic layer has lower magnetization, coercivity, and magnetic anisotropy, in comparison to the top magnetic layer. Further improvements in SNR and thermal stability are achieved using synthetic ferrimagnetic media. The selection of proper thickness and composition of the initial magnetic layer is important for the high performance of the synthetic ferrimagnetic media.