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High Curie temperatures in ferromagnetic Cr-doped AlN thin films

D. Kumar·J. Antifakos·M. G. Blamire·Z. H. Barber
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Abstract

Al1-xCrxN thin films with $0.02\le x \le 0.1$ were deposited by reactive co-sputtering onto c-plane (001) sapphire. Room-temperature ferromagnetism with a coercive field of 85 Oe was observed in samples with chromium contents as low as x = 0.027 (2.7%). With increasing Cr content the mean magnetic moment is strongly suppressed, with a maximum saturation moment of 0.62 and 0.71 $μ_B$ per Cr atom at 300 and 50 K respectively. We show that the Curie temperature of Al1-xCrxN for x = 0.027 is greater than 900 K.

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D. Kumar, J. Antifakos, M. G. Blamire, Z. H. Barber. 2004-04-19. High Curie temperatures in ferromagnetic Cr-doped AlN thin films. https://doi.org/10.1063/1.1763216

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