skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Small-angle neutron scattering study of a magnetically inhomogeneous amorphous alloy with reentrant behavior

Abstract

Small-angle neutron scattering (SANS) measurements have been performed on an archetypal reentrant amorphous ferromagnet Fe{sub 91}Zr{sub 9} over the Q range 0.003 A{sup -1}<Q<0.2 A{sup -1} and temperatures between 10 and 300 K at fixed values of magnetic field H=0, 0.26, 0.5, and 4 T. Contrast matching experiments have also been carried out at room temperature before and after immersing the ribbons in deuterium oxide. The results of these experiments demonstrate that the surface effects tend to be important only for Q<0.006 A{sup -1}. Application of a field H=4 T much larger than that corresponding to the technical saturation of magnetization allows an unambiguous separation of the nuclear and magnetic scattering contributions to the measured SANS intensity. The standard practice of analyzing the Q-dependence of the SANS intensity of reentrant ferromagnetic systems in terms of the expression, Lorentzian plus Lorentzian-squared, revealed that in the present case, this expression fails to adequately describe the observed variation of the magnetic component of the SANS intensity with Q, even in the reentrant state. By comparison, a model, in which spin clusters of average size (R{approx_equal}2 nm) with a relatively narrow size distribution coexist with clusters of larger average size and wider size distribution,more » reproduces the magnetic scattering over the entire Q range at all temperatures. While the size of the smaller clusters does not change with temperature, the larger ones grow as the temperature is increased from the reentrant state at low temperatures up to the Curie temperature (T{sub C}) through the ferromagnetic regime. The present results also strongly indicate the presence of clusters at temperatures well above T{sub C} in the paramagnetic state.« less

Authors:
; ; ; ; ; ;  [1]
  1. Departamento CITIMAC, F. Ciencias, Universidad de Cantabria, 39005 Santander (Spain)
Publication Date:
OSTI Identifier:
20666304
Resource Type:
Journal Article
Journal Name:
Physical Review. B, Condensed Matter and Materials Physics
Additional Journal Information:
Journal Volume: 71; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevB.71.134413; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1098-0121
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CURIE POINT; FERROMAGNETIC MATERIALS; HEAVY WATER; IRON ALLOYS; MAGNETIC FIELDS; MAGNETIZATION; NEUTRON DIFFRACTION; PARAMAGNETISM; SMALL ANGLE SCATTERING; SPIN; TEMPERATURE RANGE 0273-0400 K; ZIRCONIUM ALLOYS

Citation Formats

Garcia Calderon, R, Fernandez Barquin, L, Kaul, S N, Gomez Sal, J C, Gorria, Pedro, Pedersen, J S, Heenan, R K, Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo, Condensed Matter Physics and Chemistry Department, Risoe National Laboratory, DK-4000, Roskilde, and ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX. Small-angle neutron scattering study of a magnetically inhomogeneous amorphous alloy with reentrant behavior. United States: N. p., 2005. Web. doi:10.1103/PhysRevB.71.134413.
Garcia Calderon, R, Fernandez Barquin, L, Kaul, S N, Gomez Sal, J C, Gorria, Pedro, Pedersen, J S, Heenan, R K, Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo, Condensed Matter Physics and Chemistry Department, Risoe National Laboratory, DK-4000, Roskilde, & ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX. Small-angle neutron scattering study of a magnetically inhomogeneous amorphous alloy with reentrant behavior. United States. https://doi.org/10.1103/PhysRevB.71.134413
Garcia Calderon, R, Fernandez Barquin, L, Kaul, S N, Gomez Sal, J C, Gorria, Pedro, Pedersen, J S, Heenan, R K, Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo, Condensed Matter Physics and Chemistry Department, Risoe National Laboratory, DK-4000, Roskilde, and ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX. 2005. "Small-angle neutron scattering study of a magnetically inhomogeneous amorphous alloy with reentrant behavior". United States. https://doi.org/10.1103/PhysRevB.71.134413.
@article{osti_20666304,
title = {Small-angle neutron scattering study of a magnetically inhomogeneous amorphous alloy with reentrant behavior},
author = {Garcia Calderon, R and Fernandez Barquin, L and Kaul, S N and Gomez Sal, J C and Gorria, Pedro and Pedersen, J S and Heenan, R K and Departamento de Fisica, Universidad de Oviedo, 33007 Oviedo and Condensed Matter Physics and Chemistry Department, Risoe National Laboratory, DK-4000, Roskilde and ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX},
abstractNote = {Small-angle neutron scattering (SANS) measurements have been performed on an archetypal reentrant amorphous ferromagnet Fe{sub 91}Zr{sub 9} over the Q range 0.003 A{sup -1}<Q<0.2 A{sup -1} and temperatures between 10 and 300 K at fixed values of magnetic field H=0, 0.26, 0.5, and 4 T. Contrast matching experiments have also been carried out at room temperature before and after immersing the ribbons in deuterium oxide. The results of these experiments demonstrate that the surface effects tend to be important only for Q<0.006 A{sup -1}. Application of a field H=4 T much larger than that corresponding to the technical saturation of magnetization allows an unambiguous separation of the nuclear and magnetic scattering contributions to the measured SANS intensity. The standard practice of analyzing the Q-dependence of the SANS intensity of reentrant ferromagnetic systems in terms of the expression, Lorentzian plus Lorentzian-squared, revealed that in the present case, this expression fails to adequately describe the observed variation of the magnetic component of the SANS intensity with Q, even in the reentrant state. By comparison, a model, in which spin clusters of average size (R{approx_equal}2 nm) with a relatively narrow size distribution coexist with clusters of larger average size and wider size distribution, reproduces the magnetic scattering over the entire Q range at all temperatures. While the size of the smaller clusters does not change with temperature, the larger ones grow as the temperature is increased from the reentrant state at low temperatures up to the Curie temperature (T{sub C}) through the ferromagnetic regime. The present results also strongly indicate the presence of clusters at temperatures well above T{sub C} in the paramagnetic state.},
doi = {10.1103/PhysRevB.71.134413},
url = {https://www.osti.gov/biblio/20666304}, journal = {Physical Review. B, Condensed Matter and Materials Physics},
issn = {1098-0121},
number = 13,
volume = 71,
place = {United States},
year = {Fri Apr 01 00:00:00 EST 2005},
month = {Fri Apr 01 00:00:00 EST 2005}
}