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arXiv · 2104.14262

Bulk-Sensitive Spin-Resolved Resonant Electron Energy-Loss Spectroscopy (SR-rEELS): Observation of Element- and Spin-Selective Bulk Plasmons

Shin-ichi Kimura·Taishi Kawabata·Hiroki Matsumoto·Yu Ohta·Ayuki Yoshizumi·Yuto Yoshida·Takumi Yamashita·Hiroshi Watanabe·Yoshiyuki Ohtsubo·Naoto Yamamoto·Xiuguang Jin
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Abstract

We have developed a spin-resolved resonant electron energy-loss spectroscopy (SR-rEELS) in the primary energy of 0.3--1.5 keV, which corresponds to the core excitations of $2p$-$3d$ absorption of transition metals and $3d$-$4f$ absorption of rare-earths, with the energy resolution of about 100~meV using a spin-polarized electron source as a GaAs/GaAsP strained superlattice photocathode. Element- and spin-selective carrier and valence plasmons can be observed using the resonance enhancement of core absorptions and electron spin polarization. Furthermore, bulk-sensitive EELS spectra can be obtained because the primary energy corresponds to the mean free path of 1--10~nm. The methodology is expected to provide us novel information of elementary excitations by resonant inelastic x-ray scattering and resonant photoelectron spectroscopy.

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Shin-ichi Kimura, Taishi Kawabata, Hiroki Matsumoto, Yu Ohta, Ayuki Yoshizumi, Yuto Yoshida, Takumi Yamashita, Hiroshi Watanabe, Yoshiyuki Ohtsubo, Naoto Yamamoto, Xiuguang Jin. 2021-04-29. Bulk-Sensitive Spin-Resolved Resonant Electron Energy-Loss Spectroscopy (SR-rEELS): Observation of Element- and Spin-Selective Bulk Plasmons. https://doi.org/10.1063/5.0055435

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