The Study On Magneto-transport Properties And Anisotropy Of Quaternary Ferromagnetic Semiconductor (Ga, Mn) (As, Sb)

In this paper, the growth, magneto-transport properties and magnetic anisotropy of quaternary ferromagnetic semiconductor (Ga, Mn) (As, Sb) was studied.First, (Ga, Mn) (As, Sb) films with different Sb contents were grown by low temperature molecular beam epitaxy (LT-MBE), the values of nominal Mn content was estimated. SQUID measurements gives the magnetic hysteresis loop of annealing group and as-grown group of (Ga, Mn) (As, Sb) films, it proved that quaternary ferromagnetic semiconductor (Ga, Mn) (As, Sb) exists ferromagnetic. On the one hand, the effective Mn content can be calculated by the saturation magnetization, on the other hand, the ferromagnetic transition temperature Tc of films can be given through Mr-T curve. xeff and Tc aganist Sb content σ variation curves indicate that xeff and Tc have the same trend with increasing of Sb incorporated, firstly increased then decreased. The Hall measurements makes a thorough study on anisotropic effects of different Sb content (Ga, Mn) (As, Sb) films. We add a crossed-term on expression of anisotropic magnetoresistance (AMR) wich based on the AMR of (Ga, Mn) As. According to the equations the fitting curves and the experimental lines fit very well. The crossed-term can not be neglected either for (Ga, Mn) As or (Ga, Mn) (As,Sb) Since the incorporation of Sb destroyed the symmetry of the (Ga, Mn) (As,Sb) so that change the anisotropy coefficient of (Ga, Mn) (As,Sb). With the increasing of Sb content, the anisotropy coefficients of (Ga, Mn) (As, Sb) close to zero, so the anisotropic characteristics gradually disappear.