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Orbital order induced metal-insulator transition in (La,Ca)MnO3

Bas B. Van Aken·Auke Meetsma·Y. Tomioka·Y. Tokura·Thomas T. M. Palstra
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Abstract

We present evidence that the insulator to metal transition in (La,Ca)MnO3 near x~0.2 is driven by the suppression of coherent Jahn-Teller distortions, originating from d type orbital ordering. The orbital ordered state is characterised by large long-range Q2 distortions below To*-o'. Above To*-o' we find evidence for coexistence between an orbital-ordered and -disordered state. This behaviour is discussed in terms of electronic phases of an orbital ordered insulating and orbital-disordered metallic states.

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Bas B. Van Aken, Auke Meetsma, Y. Tomioka, Y. Tokura, Thomas T. M. Palstra. 2002-04-04. Orbital order induced metal-insulator transition in (La,Ca)MnO3. https://doi.org/10.1103/physrevlett.90.066403

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