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arXiv · 1001.3719

Magnetic phase transitions in SmCoAsO

V. P. S. Awana·I. Nowik·Anand Pal·K. Yamaura·E. Takayama-Muromachi·I. Felner
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Abstract

Magnetization, x-ray diffraction and specific-heat measurements reveal that SmCoAsO undergoes three magnetic phase transitions. A ferromagnetic transition attributed to the Co ions, emerges at TC=57 K with a small saturation moment of 0.15muB/Co. Reorientation of the Co moment to an antiferromagnetic state is obtained at TN2=45 K. The relative high paramagnetic effective moment Peff=1.57 MuB/Co indicates an itinerant ferromagnetic state of the Co sublattice. The third magnetic transition at TN1=5 K is observed clearly in the specific-heat study only. Both magnetic and 57Fe Mossbauer studies show that substitution of small quantities of Fe for Co was unsuccessful.

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V. P. S. Awana, I. Nowik, Anand Pal, K. Yamaura, E. Takayama-Muromachi, I. Felner. 2010-01-21. Magnetic phase transitions in SmCoAsO. https://doi.org/10.1103/physrevb.81.212501

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