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arXiv · 0710.3723

Continuous first order orbital order-disorder transition in Nd1-xCaxMnO3

C. V. Colin·A. J. C. Buurma·M. v. Zimmermann·T. T. M. Palstra
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Abstract

The nature of the cooperative Jahn-Teller (JT) transition accompanied by orbital order-disorder in Nd1-xCaxMnO3 has been studied by high temperature (300 - 1200K) synchrotron and laboratory X-ray powder diffraction in the low doping region (0<x<0.1). For very low doping a large temperature range of phase coexistence associated with a first-order transition has been observed, resembling a martensitic transformation. The transition appears continuous because of a gradual evolution of the volume fractions of the phases over a broad temperature interval. The first-order nature of the transition and the phase coexistence is suppressed with increasing of doping.

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C. V. Colin, A. J. C. Buurma, M. v. Zimmermann, T. T. M. Palstra. 2007-10-19. Continuous first order orbital order-disorder transition in Nd1-xCaxMnO3. https://doi.org/10.1088/0953-8984%2F20%2F43%2F434223

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