Growth of (Ga,Mn)As on GaAs(001) and (311)A in a high-mobility MBE system

We demonstrate the possibility to produce both GaAs/AlGaAs heterostructures with high electron mobilities and (Ga,Mn)As by molecular beam epitaxy (MBE) in the same growth chamber. The (Ga,Mn)As samples have been grown on (0 0 1) and (3 1 1)A GaAs substrates and show state of the art quality. Immediately after (Ga,Mn)As growth, two-dimensional electron systems have been produced which show electron mobilities of up to . Photoluminescence measurements reveal that no manganese has been incorporated into these samples. Magnetotransport measurements on (Ga,Mn)As samples show an anomalous Hall effect if the magnetic field is oriented perpendicular to the sample surface and a giant planar Hall effect if the field is parallel to the surface. By rotating the sample in the field, the magnetic anisotropy of the samples can be analyzed. The high quality GaAs/AlGaAs heterostructures that can be produced in the same MBE system provide an excellent basis for future experiments combining high-mobility heterostructures with ferromagnetic semiconductors

Magnetic anisotropy of Ga1–xMnxAs thin films on GaAs (311)A probed by ferromagnetic resonance

We have studied the magnetic anisotropy of Ga1–xMnxAs thin films grown by low-temperature molecular beam epitaxy on GaAs (311)A substrates by means of ferromagnetic resonance spectroscopy. The angular dependence of the ferromagnetic resonance fields observed can be explained by two main contributions to the magnetic anisotropy: a cubic magnetic anisotropy field oriented along the crystallographic axes caused by the symmetry of the GaAs host lattice, and an effective uniaxial magnetic anisotropy field along [311] presumably caused by the homoepitaxial growth of the layer. Additional smaller magnetic anisotropy contributions are discussed. Consequently, the dominating magnetic anisotropy of Ga1–xMnxAs on GaAs (311)A substrate appears to have the same origin as on GaAs (100) substrate