Magnetic and transport properties of the ferromagnetic semiconductor heterostructures (In,Mn)As/(Ga,Al)Sb

We have investigated the magnetic and transport properties of (In,Mn)As thi n films grown on a (Ga,Al)Sb layer. Strong perpendicular magnetic anisotrop y is observed for the (In,Mn)As layer, the thickness of which is less than the critical value required for relaxation of lattice-mismatch-induced stra in. The anomalous Hall coefficient is found to be approximately proportiona l to the square of resistivity in the low-field region. Large negative magn etoresistance is found to occur over a magnetic field range significantly w ider than that for the ferromagnetic hysteresis loop. [S0163-1829 (98)04344 -6].