High perpendicular anisotropy and magneto-optical activities in ordered Co3Pt alloy films

Abstract

The origin of the large perpendicular magnetic anisotropy constant Ku of Co3Pt alloy thin films is discussed. The films deposited onto Al2O3(0001), Al2O3(112̄0), and MgO(111) substrates held at 230–450 °C during deposition exhibit Ku of the order of 107 erg/cm3 at room temperature. While the one dimensional long range order parameter S estimated by x-ray diffraction is very consistent with the development of the perpendicular magnetic anisotropy in the films deposited at 380–450 °C, very little evidence is found to suggest the correlation between S and Ku for the lower deposition temperature range (230–380 °C). To explain this, a short range ordering is suggested to be responsible for the origin of Ku, similar to the cases in Pt72Co28 alloys. The magneto-optical polar Kerr activity of ordered Co3Pt film is found to be enhanced for both θK and ηK in the photon energy range from 2 to 4 eV.

Soliton solution for the spin current in a ferromagnetic nanowire

“…(21) will be described below. The properties of envelope soliton solution (21) are characterized by the width 1/ (2D 1R ), the wave number k s = −2D 1I , the initial center position −x 0 /D 1R , and the envelope velocity…”

“…These results show that the background has almost no effect on the trapping condition in the special case A c << k c and µ 1 << ν 1 . For the materials of Co 3 Pt alloy films [21] which has high perpendicular anisotropy, we chose H K = 1 × 10 4 Oe, A = 1.0×10 −6 erg/cm, 4πM s = 1×10 2 Oe, γ = 1.76×10…”

“…With this new form of spin torque, the nonlinear excitations on the background of ground state are studied, such as the unique features of Néel wall motion in a nanowire [15], kink soliton solution and the domain wall dynamics in a biaxial ferromagnet [16], bulk spin excitations [7,15], and magnetic soliton solutions for isotropic case [17] and uniaxial anisotropic case [18]. It is well known that the nonlinear spin wave and magnetic solitons are always topic research in confined ferromagnetic materials [19,20,21,22] due to the interaction between spin-polarized current and local magnetization, especially the generation and detection of magnons excitation [20] in a magnetic multilayer.…”

Magnetic properties and structure of (FexCo100−x)3Pt alloy thin films

“…Recently, the m-DO 19 phase of Co 3 Pt has been realized in thin film form on Al 2 O 3 (0 0 Á 1) substrates held at certain growth temperatures and it is found to possess large perpendicular magnetic anisotropy (10 7 erg/cc) [1,2]. On the other hand, Fe 3 Pt films on Al 2 O 3 (0 0 Á 1) substrate is found fcc (L1 2 ) phase with /1 1 1S orientation and exhibits large inplane 6-fold magnetic anisotropy [3].…”

Effect of additional elements on compositional modulated atomic layered structure of hexagonal Co80Pt20 alloy films with superlattice diffraction

“…[1][2][3][4][5][6] In practice, for current perpendicular recording medium, granular film which consists of CoPt alloy and oxide has been widely used. To increase thermal stability of the recording medium, the enhancement of K u is indispensable.…”