Retrieval of phase information in neutron reflectometry

Authors

V.-O. de Haan, Delft University of Technology
A. A. van Well, Delft University of Technology
Shireen Adenwalla, University of Nebraska-LincolnFollow
G. P. Felcher, Argonne National Laboratory

Date of this Version

1995

Citation

PHYSICAL REVIEW B VOLUME 52, NUMBER 15, 15 OCTOBER 1995

Comments

Copyright 1995 The American Physical Society

Abstract

Neutron reflectometry can determine unambiguously the chemical depth profile of a thin film if both phase and amplitude of the reflectance are known. The recovery of the phase information is achieved by adding to the unknown layered structure a known ferromagnetic layer. The ferromagnetic layer is magnetized by an external magnetic field in a direction lying in the plane of the layer and subsequently perpendicular to it. The neutrons are polarized either parallel or opposite to the magnetic field. In this way three measurements can be made, with different (and known) scattering-length densities of the ferromagnetic layer. The reflectivity obtained from each measurement can be represented by a circle in the (complex) reflectance plane. The intersections of these circles provide the reflectance.