Mbe growth and magnetic properties of GaSb/MnSb superlattices

We have grown a 37-period GaSb(25 Å)/MnSb(2 Å) superlattice on GaAs(001) substrate with 1000 Å GaSb buffer layer by solid-source molecular beam epitaxy. We have observed that the streaky RHEED patterns of GaSb and MnSb were maintained even when the growth was finished in 37 periods, indicating 2-dimensional layer-by-layer growth of MnSb on GaSb or vice versa. Interestingly, a GaSb(25 Å)/MnSb(2 Å) superlattice showed ferromagnetic ordering up to above 400 K, with a coercive field of 380 Oe at 10 K.