Micromagnetic simulation of effect of stress-induced anisotropy in soft magnetic thin films

Abstract

The effect of stress in soft magnetic thin films, in particular, on the in-plane anisotropy, has been studied, based on the analysis of the magnetoelastic energy associated with the stress. The easy-axis directions and the effective anisotropy constants have been identified, as functions of the stress, the magnetostriction coefficients of the material, and the growth texture of the film. The magnetoelastic energy has been combined into an existing micromagnetic model to simulate the magnetization of thin films with various materials, stress states, and growth textures. Simulation results of static magnetic domain structures are in agreement with the theoretical predictions.

400-fold reduction in saturation field by interlayering

“…The relationships among stress, magnetostriction, magnetic anisotropy, growth, and processing of thin magnetic films is a topic of long-standing interest in magnetism. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] The impact on the saturation field of the sense layer is an important issue for magnetic sensors based on magnetoresistance effects. To detect small magnetic fields, these sensors need to incorporate a sense layer that is magnetically soft.…”

The incorporation of the Cauchy stress matrix tensor in micromagnetic simulations

“…12,34 As the voltage is increased to +0.1 V, the maximum stress along the x-axis increases to 0.15 GPa. This domain structure is frequently observed in similar elements.…”

“…[11][12][13][14][15][16][17][18][19] Often in theoretical studies and analysis of results, stress effects are included in magnetic simulations by incorporating an extra energy term into the free energy of the system. [11][12][13][14][15][16][17][18][19] Often in theoretical studies and analysis of results, stress effects are included in magnetic simulations by incorporating an extra energy term into the free energy of the system.…”

Voltage Assisted Perpendicular Write Head

“…The material is Fe Co with magnetostriction coefficients: and . The Gilbert equation with a damping constant is used to solve the dynamic magnetization configurations [3], [4]. A perpendicular medium with an ideal soft magnetic underlayer (SUL) is assumed.…”