Spin polarized neutron reflectivity measurements on Heusler [Co2MnGe/V]n multilayers

We report spin polarized neutron reflectivity measurements of the magnetic order in [Co2MnGe/V](n) multilayers prepared by rf sputtering. In the neutron reflectivity scans we detect a half-order magnetic Bragg peak which can be suppressed by applying a weak external magnetic field. The half-order peak provides clear evidence for a doubling of the multilayer period due to antiferromagnetic (at) superlattice ordering in [Co2MnGe/V](n). The of ground state exists in the thickness range 1.5 nm less than or equal to d(V) less than or equal to 3 nm without any indication of an oscillatory character of the interlayer exchange interaction. The antiferromagnetic ordering temperature T-N is low compared to the ferromagnetic ordering temperature of a single Co2MnGe film. (C) 2004 Elsevier Ltd. All rights reserved.