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Statut |
Confirmé |
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Série |
SEM-BESSON |
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Domaines |
cond-mat |
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Date |
Lundi 9 Octobre 2006 |
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Heure |
10:30 |
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Institut |
IMPMC |
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Salle |
Salle de Conferences, Bat. 15, Campus Boucicaut, 140 rue de Lourmel |
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Nom de l'orateur |
Revcolevschi |
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Prenom de l'orateur |
Alexandre |
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Addresse email de l'orateur |
alexandre [dot] revcolevschi [at] lpces [dot] u-psud [dot] fr |
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Institution de l'orateur |
Laboratoire de Physico- Chimie de l’Etat Solide, University of Paris XI – Orsay |
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Titre |
Crystal growth, characterization and some physical properties of correlated electron oxide crystals |
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Résumé |
In the last few years our solid state chemistry ORSAY group has carried out crystal growth experiments in various correlated electron oxide systems using the image-furnace floating-zone technique developed in the laboratory, and has studied various physical properties of the resulting cm-size crystals.
The studies have mostly concerned oxides such as low dimensionality cuprates (Bi2CuO4 ; superconducting La2-xSrxCuO4 ; pure and doped spin-Peierls CuGeO3 ; copper chain systems such as SrCuO2, Sr2CuO3, BaCu2Si2O7 ; pure and doped spin ladder Sr14Cu24O41), nickelate La2NiO4, cobaltates La2CuO4 and LaCoO3, CMR manganites (pure and substituted La1-xSrxMnO3, (La,Sr)3Mn2O7) and, more recently, geometrically frustated magnetic compounds of pyrochlore structure such as Yb2Ti2O7 or Gd2Ti2O7.
Crystal growth conditions (growth rate, atmospheres, oxygen partial pressure…) will be briefly reviewed for these various compounds and data from neutron diffraction experiments, carried out to assess crystalline perfection will be presented.
Possible segregation of dopants during growth of some of the above compounds as well as oxygen non-stoichiometry will be discussed; influence of this segregation and of oxygen non-stoichiometry on the modification of physical properties will be analyzed. |
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Numéro de preprint arXiv |
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Commentaires |
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