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arXiv · 1203.2991

Oxygen vacancy enhanced room temperature ferromagnetism in Al-doped MgO nanoparticles

Debabrata Mishra·Balaji P. Mandal·Rupam Mukherjee·Ratna Naik·Gavin Lawes·Boris Nadgorny
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Abstract

We have investigated the room temperature ferromagnetic order that develops in Al-substituted magnesium oxide, Mg(Al)O, nanoparticles with Al fractions of up to 5 at.%. All samples, including undoped MgO nanoparticles, exhibit room temperature ferromagnetism, with the saturation magnetization reaching a maximum of 0.023 emu/g at 2 at.% of Al. X-ray photoelectron spectroscopy identifies the presence of oxygen vacancies in both doped and undoped MgO nanoparticles, with the vacancy concentration increasing upon vacuum annealing of Mg(Al)O, resulting in two-fold enhancement of the saturation magnetization for 2 at.% Al-doped MgO. Our results suggest that the oxygen vacancies are largely responsible for room temperature ferromagnetism in MgO.

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Debabrata Mishra, Balaji P. Mandal, Rupam Mukherjee, Ratna Naik, Gavin Lawes, Boris Nadgorny. 2012-03-14. Oxygen vacancy enhanced room temperature ferromagnetism in Al-doped MgO nanoparticles. https://doi.org/10.1063/1.4804425

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