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arXiv · 2303.05135

Resonant Inelastic X-ray Scattering from Electronic Excitations in $\alpha$-RuCl$_3$ Nanolayers

Zichen Yang·Lichen Wang·Sourav Laha·Dong Zhao·Mingdi Luo·Achim Güth·Takashi Taniguchi·Kenji Watanabe·Bettina V. Lotsch·Jurgen H. Smet·Matteo Minola·Hlynur Gretarsson·Bernhard Keimer
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Abstract

We present Ru $L_3$-edge resonant inelastic x-ray scattering (RIXS) measurements of spin-orbit and d-d excitations in exfoliated nanolayers of the Kitaev spin-liquid candidate RuCl$_3$. Whereas the spin-orbit excitations are independent of thickness, we observe a pronounced red-shift and broadening of the d-d excitations in layers with thickness below $\sim$7 nm. Aided by model calculations, we attribute these effects to distortions of the RuCl$_6$ octahedra near the surface. Our study paves the way towards RIXS investigations of electronic excitations in various other 2D materials and heterostructures.

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Zichen Yang, Lichen Wang, Sourav Laha, Dong Zhao, Mingdi Luo, Achim Güth, Takashi Taniguchi, Kenji Watanabe, Bettina V. Lotsch, Jurgen H. Smet, Matteo Minola, Hlynur Gretarsson, Bernhard Keimer. 2023-03-09. Resonant Inelastic X-ray Scattering from Electronic Excitations in $\alpha$-RuCl$_3$ Nanolayers. https://doi.org/10.1103/physrevb.108.l041406

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