Tailoring magnetism in L10-ordered nanostructures: Perspectives for magnetic recording beyond 1Tb/in2
This topical section in physica status solidi (a) deals with recent progress achieved in the development of high-density recording systems based on nanoparticles of the hard intermetallic compounds L10-FePt and L10-CoPt. Nano-granular and bit-patterned films of these compounds are hopeful candidates for an extension of magnetic recording densities beyond the 1 Tb∕in2 range. The so-called trilemma problem: thermal stability, writability, and signal-to-noise ratio, is discussed in detail on the basis of thermally assisted recording and composite nanopatterns of FePt∕α-Fe.
The methods of the formation of FePt-based nanosystems by advanced techniques, as chemical synthesis, lithography, sputtering and rapid thermal annealing are outlined. The characterization techniques of the microstructures of nanoparticles by transmission electron microscopy and X-ray absorption spectroscopy are presented. The role of graded composites and encapsulation of FePt particles by nonferromagnetic elements and its effects on spin and orbital moments are discussed. Micromagnetism and simulation techniques are applied to analyse the reversal of magnetization of individual nanoparticles.