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arXiv · 0707.3112

The Ba2LnFeNb4O15 Tetragonal Tungsten Bronze: towards RT composite multiferroics

M. Josse·O. Bidault·F. Roulland·E. Castel·A. Simon·D. Michau·R. Von der Muhll·O. Nguyen·M. Maglione
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Abstract

Several Niobium oxides of formula Ba2LnFeNb4O15 (Ln = La, Pr, Nd, Sm, Eu, Gd) with the Tetragonal Tungsten Bronze (TTB) structure have been synthesised by conventional solid-state methods. The Neodymium, Samarium and Europium compounds are ferroelectric with Curie temperature ranging from 320 to 440K. The Praseodymium and Gadolinium compounds behave as relaxors below 170 and 300 K respectively. The Praseodymium, Neodymium, Samarium, Europium and Gadolinium compounds exhibit magnetic hysteresis loops at room temperature originating from traces of a barium ferrite secondary phase. The presence of both ferroelectric and magnetic hysteresis loops at room temperature allows considering these materials as composites multiferroic. Based on crystal-chemical analysis we propose some relationships between the introduction of Ln3+ ions in the TTB framework and the chemical, structural and physical properties of these materials.

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M. Josse, O. Bidault, F. Roulland, E. Castel, A. Simon, D. Michau, R. Von der Muhll, O. Nguyen, M. Maglione. 2008-06-26. The Ba2LnFeNb4O15 Tetragonal Tungsten Bronze: towards RT composite multiferroics. https://arxiv.org/abs/0707.3112

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