Thermal Stability Enhancement of Perpendicular Media With High-Order Uniaxial Anisotropy

Abstract

The effect of second-order uniaxial anisotropy energy 2 on thermal stability and writability of perpendicular media has been studied. Due to the high orientation of crystalline easy axes, both energy barrier and dynamic coercivity of perpendicular media increases with 2 . With relatively more increase in energy barrier, improvement of the tradeoff between thermal stability and writability can be achieved by increasing 2 . The field angle dependence with nonzero 2 is also quantitatively investigated.

Impact of Anisotropic Exchange on M-H Loops: Application to ECC Media

“…The usual exchange parameter is expressed as A=Jd 2 , where d 2 is the cross-sectional area of a grain. Singleion uniaxial anisotropy (K), fourth-order uniaxial anisotropy (K 2 ) [7], and magnetostatic interactions are also included. Zero temperature calculations were performed using a Suzuki-Trotter rotation-matrix method [8] with a damping parameter =1.…”

Nanostructure of CoPtCr&ndash;SiO<SUB>2</SUB> Granular Films for Magnetic Recording Media

“…1,2) For realization of high density recording beyond 400 Gbit/ inch 2 , the application of higher order terms such as K u2 (K u ¼ K u1 þ K u2 þ Á Á Á) is advantageous, [3][4][5][6][7] where total magnetic anisotropy energy is described as E ¼ K u1 sin 2 þ K u2 sin 4 þ Á Á Á. The alloy CoPtCr is one of the attractive materials from this standpoint because Shimatsu et al recently reported that the value of K u2 of CoPtCr could be easily controlled by a choice of seed layers.…”