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arXiv · 1612.02235

Intrinsic Ferromagnetism in the Diluted Magnetic Semiconductor Co:TiO$_2$

H. Saadaoui·X. Luo·Z. Salman·X. Y. Cui·N. N. Bao·P. Bao·R. K. Zheng·L. Tseng·Y. H. Du·T. Prokscha·A. Suter·T. Liu·Y. R. Wang·S. Li·J. Ding·S. P. Ringer·E. Morenzoni·J. B. Yi
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Abstract

Here we present a study of magnetism in \CTO\ anatase films grown by pulsed laser deposition under a variety of oxygen partial pressures and deposition rates. Energy-dispersive spectrometry and transition electron microscopy analyses indicate that a high deposition rate leads to a homogeneous microstructure, while very low rate or postannealing results in cobalt clustering. Depth resolved low-energy muon spin rotation experiments show that films grown at a low oxygen partial pressure ($\approx 10^{-6}$ torr) with a uniform structure are fully magnetic, indicating intrinsic ferromagnetism. First principles calculations identify the beneficial role of low oxygen partial pressure in the realization of uniform carrier-mediated ferromagnetism. This work demonstrates that Co:TiO$_2$ is an intrinsic diluted magnetic semiconductor.

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H. Saadaoui, X. Luo, Z. Salman, X. Y. Cui, N. N. Bao, P. Bao, R. K. Zheng, L. Tseng, Y. H. Du, T. Prokscha, A. Suter, T. Liu, Y. R. Wang, S. Li, J. Ding, S. P. Ringer, E. Morenzoni, J. B. Yi. 2016-12-07. Intrinsic Ferromagnetism in the Diluted Magnetic Semiconductor Co:TiO$_2$. https://doi.org/10.1103/physrevlett.117.227202

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