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arXiv · 1711.01781

Observation of Intrinsic Half-metallic Behavior of CrO$_2$ (100) Epitaxial Films by Bulk-sensitive Spin-resolved PES

Hirokazu Fujiwara·Masanori Sunagawa·Kensei Terashima·Tomoko Kittaka·Takanori Wakita·Yuji Muraoka·Takayoshi Yokoya
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Abstract

We have investigated the electronic states and spin polarization of half-metallic ferromagnet CrO$_2$ (100) epitaxial films by bulk-sensitive spin-resolved photoemission spectroscopy with a focus on non-quasiparticle (NQP) states derived from electron-magnon interactions. We found that the averaged values of the spin polarization are approximately 100% and 40% at 40 K and 300 K, respectively. This is consistent with the previously reported result [H. Fujiwara et al., Appl. Phys. Lett. 106, 202404 (2015).]. At 100 K, peculiar spin depolarization was observed at the Fermi level ($E_{F}$), which is supported by theoretical calculations predicting NQP states. This suggests the possible appearance of NQP states in CrO$_2$. We also compare the temperature dependence of our spin polarizations with that of the magnetization.

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Hirokazu Fujiwara, Masanori Sunagawa, Kensei Terashima, Tomoko Kittaka, Takanori Wakita, Yuji Muraoka, Takayoshi Yokoya. 2017-11-06. Observation of Intrinsic Half-metallic Behavior of CrO$_2$ (100) Epitaxial Films by Bulk-sensitive Spin-resolved PES. https://doi.org/10.1016/j.elspec.2017.02.003

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