Valence-electron transfer and a metal-insulator transition in a strongly correlated perovskite oxide

Abstract

We present transport and thermal data for the quadruple-perovskites MCu3(Ti1-xRux)4O12 where 0 < x < 1. A metal-insulator transition (MIT) occurs for Ru concentrations x~0.75. At the same time, the Cu2+ antiferromagnetic state is destroyed and it's magnetic entropy suppressed by Ru on a 1:1 basis. This implies that each Ru transfers an electron to a Cu ion and thus the MIT correlates with filling the Cu 3d shell. The Cu spin entropy in this strongly correlated electron material provides a unique probe among MIT systems.

arXiv comment15 pages, 4 figures, 1 table

References in corpus (3)

• A first-principles study of the structure and lattice dielectric response of CaCu{3}Ti{4}O{12}
• Structural and magnetic aspects of the metal insulator transition in Ca${}_{2-x}$Sr${}_x$RuO${}_4$
• Antiferromagnetism in CaCu${}_3$Ti${}_4$O${}_{12}$ studied by magnetic Raman spectroscopy

Cited by in corpus (8)

• Heavy-Mass Behavior of Ordered Perovskites ACu3Ru4O12 (A = Na, Ca, La)
• On the magnetism of Ln{2/3}Cu{3}Ti{4}O{12} (Ln = lanthanide)
• Correlation effects in CaCu3Ru4O12
• Intermediate-valence behavior of the transition-metal oxide CaCu${}_3$Ru${}_4$O${}_{12}$
• Evidence for a Ru${}^{4+}$ Kondo Lattice in LaCu${}_3$Ru${}_4$O${}_{12}$
• High-field magnetization and magnetoresistance of the $A$-site ordered perovskite oxide CaCu${}_3$Ti${}_{4-x}$Ru${}_x$O${}_{12}$~($0\le x\le 4$)
• Temperature dependence of the electronic structure of A-site ordered perovskite CaCu${}_3$Ti${}_4$O${}_{12}$: Angle-integrated and -resolved photoemission studies
• Variation of strong correlation effects in A-site ordered perovskites CaCu3Ti4-xRuxO12: Photoemission and inverse photoemission studies