RT Journal Article
T1 Direct measurements of the correlation between reentrant ferromagnetism and lattice expansion in FeCuZr alloys
A1 Martinez, A.
A1 Spottorno Giner, Jorge
A1 Figueroa, A.
A1 Bartolome, F.
A1 Garcia, L. M.
A1 Prestipino, C.
A1 Hernando Grande, Antonio
A1 Crespo del Arco, Patricia
AB Amorphous metastable alloy of nominal composition [Fe_(0.5)Cu_(0.5)]_(87)Zr_(13) has been synthesized by high-energy ball milling. The alloy exhibit a ferromagnetic behavior with a Curie Temperature of T_(C)=255 K, as determined from low-field measurements whereas no transition to a paramagnetic state is observed under high- enough applied magnetic fields. The evolution of hysteresis loops with temperature as well as thermoremanence measurements indicate an anomalous magnetic behavior characterized by a spontaneous increase in the magnetization values as well as by a magnetic hardening when the temperature is increased above T_(C). These effects are strongly correlated with a dilation of the Fe-Fe nearest-neighbor distances, as determined from extended x-ray absorption fine structure (EXAFS) studies. EXAFS results indicate an almost negligible thermal expansion at temperatures below T_(C) while normal thermal expansion takes place at higher temperatures. Such expansion seems to promote a reinforcement of the ferromagnetic interactions among Fe-Fe atoms that would account for the observed spontaneous increase in the magnetization as well as for the evolution of the coercive field.
PB American Physical Society
SN 1098-0121
YR 2010
FD 2010-07-14
LK https://hdl.handle.net/20.500.14352/42610
UL https://hdl.handle.net/20.500.14352/42610
LA eng
NO ©2010 The American Physical Society.This work was supported by Spanish MICINN under Projects No. MAT2009-14741-C02-01 and No. MAT2008- 01077, and Consolider-Ingenio in Molecular Nanoscience under Project No. CSD2007- 00010; and DGA by means of IMANA and CAMRADS. A.I.F acknowledges a CSIC-JAE Predoc grant.
NO Spanish MICINN
NO Consolider-Ingenio in Molecular Nanoscience
NO DGA
DS Docta Complutense
RD 7 abr 2025