Temperature dependence of magnetic anisotropy in ferromagnetic (Ga,Mn)As films: Investigation by the planar Hall effect

Anisotropy of magnetoresistance in Be Co-doped GaMnAs

“…These data indicate that the direction of easy axis of magnetization remains constant in all investigated temperature range. Such behavior of easy axis of magnetization in GaMnAs:Be is also different from data observed in GaMnAs grown on GaAs substrate by LT MBE, for which rotation of easy axis from /10 0S to /110S crystalline direction at the temperature 30-40 K has been detected by magnetoresistance [7,11], the planar Hall Effect [13] and direct magnetization measurements [14]. This reorientation of easy axis in GaMnAs is the result of competition between uniaxial and biaxial contributions to the magnetic anisotropy.…”

Spin-orbit coupling effect in (Ga,Mn)As films: Anisotropic exchange interactions and magnetocrystalline anisotropy

“…[11][12][13][14][15][16][17][18] In spite of different experimental conditions, the in-plane uniaxial anisotropy was observed for (Ga,Mn)As films in a thickness range from 25 nm (Ref. 20) to 500 nm, 16 irrelevant with respect to the surface condition.…”

“…[1][2][3] In the latter case the spin-orbit coupling (SOC) makes the valence states close to E F sensitive to lattice distortions and is in that way responsible for the in-plane MCA due to compressive strains originating from the lattice mismatch between the (Ga,Mn)As film and GaAs substrate. [7][8][9][10][11][12][13][14][15][16][17] As soon as the spin polarization of the valence bands becomes rather small, the MCA in (Ga,Mn)As is discussed in terms of anisotropic exchange interactions of the Mn atoms. 2,3,7 The strength of the MCA depends on the hole concentration introduced by the Mn impurity atoms 2, 11,18,19 as well as on the variation of the equilibrium lattice parameter of (Ga,Mn)As, which increases with increasing Mn content and results thus in a larger lattice mismatch with the GaAs substrate.…”

Influence of Epitaxial Strain on Magnetic Anisotropy in (Ga,Mn)As

“…• and the ratio of Our results show that the parameter B 3 , which is sometimes assumed to be negligible [6], is important in this case. It should be noticed that even small changes of B 3 could lead to pronounced changes in the shape of hysteresis loops and one needs to care about discrete representation of the angle φ in computational simulations and numerical artifacts.…”