Patterned media: a viable route to 50 Gbit/in/sup 2/ and up for magnetic recording?

Signal-to-noise ratios in recorded patterned media

“…This is mainly due to the reduced transition noise as compared to that from granular continuous media, and because of the improved thermal stability of the individual magnetic islands [1,2]. Record and read-out measurements on patterned recording media with bit spacings as small as 70 nm (140 GBit/in 2 ) have been demonstrated using conventional magnetic heads [2] indicating the feasibility of using them to achieve high densities.…”

“…The head field per unit current, H p , is defined by (1), and the magnetisation of individual islands is described by the vector M ¼ M cos ŷ x x þ M sin yŷ y with magnitude M, and orientation y as shown in Fig. 1.x x andŷ y are unit vectors in the x-and ydirections, respectively.…”

Recording performances in perpendicular magnetic patterned media

“…Therefore, considerable research efforts have been devoted to the fabrication of patterned media [3]. The present study aims to better understand the recording performances and noise properties of these media [4]- [6], in particular on the influences of both material properties and patterning method on the writing synchronization and noises.…”

Self-Assembled Magnetic Dots, Antidots, Dot Chains, and Stripes: Epitaxial Co on Ru(0001)

“…1,2 The physical size of a magnetic system affects its magnetic properties by altering its dimensionality, structure, surface/interface electronic structure, quantum size effects and transport, and domain/domain wall structure and motion. In addition, patterned media 3,4 with individual magnetic dots has been actively explored as an alternative route for ultrahigh density information storage, since having one bit per dot promises to improve signal-to-noise ratio significantly. Self-assembly not only offers an intrinsically simpler, faster, and less costly alternative route to lithography, but also promises thermodynamically stable structures even beyond the lithographic limits.…”

“…For example, magnetic patterned media 3,4 consisting of a magnetic dot array would require dot alignment along tracks. It would even be more demanding to produce complex spintronic devices 16 by means of self-assembly.…”