|   | 
Details
   web
Records
Author Betancourth, D.; Correa, V.F.; García, D.J.
Title Evidence of a Low Energy Anisotropy in GdCoIn_5 Type Journal Article
Year 2015 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 179 Issue 1-2 Pages 90-93
Keywords Rare earth magnetism; Antiferromagnetic transition; Anisotropy
Abstract We investigate the effects of an applied magnetic field on the magnetic properties of the antiferromagnet GdCoIn 5 . The prominent anisotropy observed in the susceptibility below TN is rapidly suppressed by a field of just a few Tesla. Further evidence of this low energy-scale is obtained from magnetoresistance and magnetostriction experiments. The lattice length, particularly, shows a sudden change below 2 T when the magnetic field is applied perpendicular to the crystallographic c^ -axis.
Address
Corporate Author Thesis
Publisher Springer US Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ pedrazp @ Serial 710
Permanent link to this record
 

 
Author Encina, S.; Pedrazzini, P.
Title Low Temperature Thermoelectric Power of Ce(Pd{1-x}Cux)2Si2 Type Journal Article
Year 2015 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 179 Issue 1-2 Pages 21-27
Keywords Heavy fermions; Antiferromagnetic transition; Thermopower; Electrical resistivity
Abstract We present the thermoelectric power S(T) of the Ce(Pd 1−x Cu x ) 2 Si 2 alloy for temperatures \(1.5\,\mathrm{K} K. We observe three characteristic features across the \(0 substitution range: two positive maxima and a negative minimum, that are typical for Ce compounds that display, or lie close to, magnetism. Our analysis of the data shows that the high- T maximum is related to the Kondo effect on excited crystal-field levels, but that the low- T one cannot be simply associated with the Kondo scale, TK . We speculate that disorder induced by alloying can be at the origin of this discrepancy and can also be responsible for the low S(T) measured at low temperatures in the \(0.2 concentration range. We have extended electrical resistivity measurements on Ce(PdCu)Si 2 ( x=0.5 ) down to T∼40 mK in applied fields as high as 16 T.
Address
Corporate Author Thesis
Publisher Springer US Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ pedrazp @ Serial 706
Permanent link to this record
 

 
Author Franco, D.G.; Carbonio, R.E.; Nieva, G.
Title Magnetic Properties of the Double Perovskites LaPbMSbO6 (M = Mn, Co, and Ni) Type Journal Article
Year 2013 Publication IEEE Transactions on Magnetics Abbreviated Journal IEEE Trans. Magn.
Volume 49 Issue 8 Pages 4594-4597
Keywords X-ray diffraction; cobalt compounds; lanthanum compounds; lead compounds; magnetisation; manganese compounds; nickel compounds; paramagnetic-antiferromagnetic transitions; space groups; superexchange interactions; LaPbCoSbO6; LaPbMnSbO6; LaPbNiSbO6; M2+ distribution; Rietveld analysis; Sb5+ distribution; X-ray powder diffraction pattern; antiferromagnetic coupling; antiferromagnetic transition; aqueous synthetic route; disorder; double perovskites; ferrimagnetic characteristics; interaction paths; magnetic ions; magnetic properties; monoclinic crystals; octahedral sites; polycrystals; space group P2 1/n; super-superexchange paths; Ions; Magnetic properties; Magnetization; Manganese; Nickel; Temperature measurement; X-ray diffraction; Antiferromagnetic materials; transition metal compounds
Abstract New double perovskites LaPbMSbO6, where M2+ = Mn2+, Co2+, and Ni2+, were synthesized as polycrystals by an aqueous synthetic route at temperatures below 1000 °C. All samples are monoclinic, space group P21/n, as it is observed from Rietveld analysis of X-ray powder diffraction patterns. The distribution of M2+ and Sb5+ among the two octahedral sites have 3% of disorder for M2+ = Ni2+, whereas for M2+ = Mn2+ and Co2+ less disorder is found. The three samples have an antiferromagnetic transition, due to the antiferromagnetic coupling between M2 + through super-superexchange paths M2+-O2--Sb5+-O2--M2+. Transition temperatures are low: 8, 10 and 17 K for Mn2+, Co2+, and Ni2 + respectively, as a consequence of the relatively long distances between the magnetic ions M2+. Besides, for LaPbMnSbO6 a small transition at 45 K was found, with ferrimagnetic characteristics, possibly as a consequence of a small disorder between Mn2+ and Sb5+. This disorder would give additional and shorter interaction paths: superexchange Mn2+-O2--Mn2+.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9464 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ pedrazp @ Serial 669
Permanent link to this record