Mesoscopic magnetic states in metallic alloys with strong electronic correlations : a percolative scenario for CeNi/sub 1-x/Cu/sub x/
We present evidence for the existence of magnetic clusters of approximately 20 Å in the strongly correlated alloy system CeNi1-xCux (0.7 ≤ x ≤ 0.2) based on small angle neutron scattering experiments as well as the occurrence of staircaselike hysteresis cycles at very low temperature (100 mK). An un...
| Authors: | ; ; ; ; ; ; |
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| Format: | Article |
| Status: | Published version |
| Publication date: | 2007 |
| Country: | Brasil |
| Institution: | UFRGS |
| Repository: | Repositório Institucional da UFRGS |
| Language: | English |
| OAI Identifier: | oai:www.lume.ufrgs.br:10183/99400 |
| Online Access: | http://hdl.handle.net/10183/99400 |
| Access Level: | Open access |
| Keyword: | Ligas de cério Ligas de cobre Materiais ferromagnéticos Aglomerados metálicos Difração de nêutrons Momentos magnéticos Histerese Transicao vitrea |
| Summary: | We present evidence for the existence of magnetic clusters of approximately 20 Å in the strongly correlated alloy system CeNi1-xCux (0.7 ≤ x ≤ 0.2) based on small angle neutron scattering experiments as well as the occurrence of staircaselike hysteresis cycles at very low temperature (100 mK). An unusual feature is the observation of long-range ferromagnetic order below the cluster-glass transition without any indication of a sharp transition at a Curie temperature. These observations strongly support a phenomenological model where a percolative process connects both magnetic states. The model can account for all the puzzling data previously obtained in this system, providing a new perspective with regard to the magnetic ground state of other alloyed compounds with small magnetic moments or weak ferromagnetism with intrinsic disorder effects. |
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