A common optical algorithm for the evaluation of specular spin polarized neutron and Mossbauer reflectivities

Using the general appl nach of Lax for multiple scattering of waves a 2 x 2 covariant expression for the reflectivity of polarized slow neutrons of a magnetic layer structure of arbitrary complexity is given including polariz ation effects of the external magnetic field. The present formalism is iden tical to the earlier published one for the (nuclear) resonant X-ray (Mossba uer) reflectivity and properly takes the effect of the external magnetic fi eld of arbitrary direction on the neutron beam into account. The form of th e reflectivity matrix allows for an efficient numerical calculation. (C) 20 01 Elsevier Science B.V. All rights reserved.