TY - JOUR
T1 - Ferromagnetism in 5f-band metamagnet UCoAl induced by Os doping
AU - Andreev, A. V.
AU - Shirasaki, K.
AU - Šebek, J.
AU - Vejpravová, J.
AU - Gorbunov, D. I.
AU - Havela, L.
AU - Daniš, S.
AU - Yamamura, T.
N1 - Funding Information:
This work was supported by the Czech Science Foundation (project 16-03593S ). The work was partly performed in MLTL ( http://mltl.eu/ ), which is supported within the program of Czech Research Infrastructures (Project No. LM2011025 ). We acknowledge the support of the High Magnetic Field Laboratory Dresden (HLD) at HZDR, member of the European Magnetic Field Laboratory (EMFL).
Publisher Copyright:
© 2016 Elsevier B.V.All rights reserved.
PY - 2016/10/5
Y1 - 2016/10/5
N2 - UCoAl is a 5f-band metamagnet with a uniquely low paramagnetic-to-ferromagnetic transition field, 0.7 T, extremely sensitive to any perturbation such as elemental substitution. Here, we study variations of magnetic properties in the UCoAl-UOsAl system on single- and polycrystalline samples with different concentration of Os. We found that osmium can substitute Co in UCoAl up to 20%, while preserving the ZrNiAl structure type. Pure UOsAl was identified as a hexagonal Laves phase, MgZn2 type. It is a weak Pauli paramagnet. Even a 2%-substitution of Os for Co in the 5f band metamagnet stabilizes ferromagnetism with the Curie temperature TC = 26 K and uranium magnetic moment μU = 0.4 μB and shifts the critical metamagnetic field to zero. Higher Os concentrations enhance both TC and μU. All magnetic response is concentrated into the c-axis; the susceptibility for magnetic field perpendicular to c is low and practically temperature-independent. Our study reflects the decisive role of the 5f-5d hybridization in the magnetism of the UCoAl-UOsAl system. This work completes the study of the alloying of UCoAl with late transition metals and indicates that the non-magnetic phase exhibiting band metamagnetism is very limited in the concentration range.
AB - UCoAl is a 5f-band metamagnet with a uniquely low paramagnetic-to-ferromagnetic transition field, 0.7 T, extremely sensitive to any perturbation such as elemental substitution. Here, we study variations of magnetic properties in the UCoAl-UOsAl system on single- and polycrystalline samples with different concentration of Os. We found that osmium can substitute Co in UCoAl up to 20%, while preserving the ZrNiAl structure type. Pure UOsAl was identified as a hexagonal Laves phase, MgZn2 type. It is a weak Pauli paramagnet. Even a 2%-substitution of Os for Co in the 5f band metamagnet stabilizes ferromagnetism with the Curie temperature TC = 26 K and uranium magnetic moment μU = 0.4 μB and shifts the critical metamagnetic field to zero. Higher Os concentrations enhance both TC and μU. All magnetic response is concentrated into the c-axis; the susceptibility for magnetic field perpendicular to c is low and practically temperature-independent. Our study reflects the decisive role of the 5f-5d hybridization in the magnetism of the UCoAl-UOsAl system. This work completes the study of the alloying of UCoAl with late transition metals and indicates that the non-magnetic phase exhibiting band metamagnetism is very limited in the concentration range.
KW - Itinerant metamagnetism
KW - UCoAl
KW - Uranium intermetallics
UR - http://www.scopus.com/inward/record.url?scp=84968779807&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84968779807&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2016.04.226
DO - 10.1016/j.jallcom.2016.04.226
M3 - Article
AN - SCOPUS:84968779807
SN - 0925-8388
VL - 681
SP - 275
EP - 282
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
ER -