Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂
The order and other properties of the magnetic phase transitions in the rare-earth (R)-cobalt Laves phases RCo₂ have been studied for R=Gd, Tb, Dy, Ho, Er, Sm, Nd, and Pr by measuring the temperature dependence of the magnetic hyperfine interaction of the nuclear probe ¹¹¹Cd on the cubic R sites usi...
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| Autores principales: | , , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
2003
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/134056 |
| Aporte de: |
| id |
I19-R120-10915-134056 |
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| record_format |
dspace |
| institution |
Universidad Nacional de La Plata |
| institution_str |
I-19 |
| repository_str |
R-120 |
| collection |
SEDICI (UNLP) |
| language |
Inglés |
| topic |
Física Magnetic phase boundaries Effects of internal magnetic fields Mössbauer effect; other γ-ray spectroscopy |
| spellingShingle |
Física Magnetic phase boundaries Effects of internal magnetic fields Mössbauer effect; other γ-ray spectroscopy Forker, M. Müller, Stefan Presa, P. de la Pasquevich, Alberto Felipe Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| topic_facet |
Física Magnetic phase boundaries Effects of internal magnetic fields Mössbauer effect; other γ-ray spectroscopy |
| description |
The order and other properties of the magnetic phase transitions in the rare-earth (R)-cobalt Laves phases RCo₂ have been studied for R=Gd, Tb, Dy, Ho, Er, Sm, Nd, and Pr by measuring the temperature dependence of the magnetic hyperfine interaction of the nuclear probe ¹¹¹Cd on the cubic R sites using the perturbed angular correlation technique. Both for heavy and light R constituents the transitions change from second order (Gd, Tb, Sm) to first order (Dy, Ho, Er, Nd, Pr) at order temperatures of 150‐200 K. For heavy R constituents, the order deduced from the hyperfine interaction is in agreement with previous investigations. The observation of first order transitions in NdCo₂ and PrCo₂, however, is unexpected. In earlier studies the transitions in these compounds are usually classified as second order transitions. Both in the heavy and the light RCo₂ the discontinuous jump of the hyperfine interaction at the first order transitions increases with decreasing order temperature. This trend implies that the Co magnetization at the transition increases with decreasing T<sub>C</sub> which can be related to the temperature dependence of the coefficient of the M⁴ term of the free energy in the Wohlfarth-Rhodes-Shimizu theory of itinerant electron magnetism. All compounds investigated presented a spread of the order temperature of ∼ 1–2 K which results in a coexistence of the paramagnetic and the magnetically ordered phase near the transition and causes a critical increase of the relative linewidth of the hyperfine frequency diverging as δ∝(1–T/T<sub>C</sub>)<sup>ε</sup> with ε = –1.0(1). |
| format |
Articulo Articulo |
| author |
Forker, M. Müller, Stefan Presa, P. de la Pasquevich, Alberto Felipe |
| author_facet |
Forker, M. Müller, Stefan Presa, P. de la Pasquevich, Alberto Felipe |
| author_sort |
Forker, M. |
| title |
Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| title_short |
Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| title_full |
Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| title_fullStr |
Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| title_full_unstemmed |
Perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt Laves phases RCo₂ |
| title_sort |
perturbed angular correlation study of the magnetic phase transitions in the rare-earth cobalt laves phases rco₂ |
| publishDate |
2003 |
| url |
http://sedici.unlp.edu.ar/handle/10915/134056 |
| work_keys_str_mv |
AT forkerm perturbedangularcorrelationstudyofthemagneticphasetransitionsintherareearthcobaltlavesphasesrco2 AT mullerstefan perturbedangularcorrelationstudyofthemagneticphasetransitionsintherareearthcobaltlavesphasesrco2 AT presapdela perturbedangularcorrelationstudyofthemagneticphasetransitionsintherareearthcobaltlavesphasesrco2 AT pasquevichalbertofelipe perturbedangularcorrelationstudyofthemagneticphasetransitionsintherareearthcobaltlavesphasesrco2 |
| bdutipo_str |
Repositorios |
| _version_ |
1764820455862042624 |