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arXiv · 0903.0225

Fundamental thickness limit of itinerant ferromagnetic SrRuO$_3$ thin films

Young Jun Chang·Choong H. Kim·S. -H. Phark·Y. S. Kim·J. Yu·T. W. Noh
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Abstract

We report on a fundamental thickness limit of the itinerant ferromagnetic oxide SrRuO$_3$ that might arise from the orbital-selective quantum confinement effects. Experimentally, SrRuO$_3$ films remain metallic even for a thickness of 2 unit cells (uc), but the Curie temperature, T$_C$, starts to decrease at 4 uc and becomes zero at 2 uc. Using the Stoner model, we attributed the T$_C$ decrease to a decrease in the density of states (N$_o$). Namely, in the thin film geometry, the hybridized Ru-d$_yz,zx$ orbitals are terminated by top and bottom interfaces, resulting in quantum confinement and reduction of N$_o$.

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Young Jun Chang, Choong H. Kim, S. -H. Phark, Y. S. Kim, J. Yu, T. W. Noh. 2009-03-02. Fundamental thickness limit of itinerant ferromagnetic SrRuO$_3$ thin films. https://doi.org/10.1103/physrevlett.103.057201

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