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arXiv · 0806.3302

Charge excitations associated with charge stripe order in the 214-type nickelate and superconducting cuprate

S. Wakimoto·H. Kimura·K. Ishii·K. Ikeuchi·T. Adachi·M. Fujita·K. Kakurai·Y. Koike·J. Mizuki·Y. Noda·A. H. Said·Y. Shvyd'ko·K. Yamada
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Abstract

Charge excitations were studied for stipe-ordered 214 compounds, La$_{5/3}$Sr$_{1/3}$NiO$_{4}$ and 1/8-doped La$_{2}$(Ba, Sr)$_{x}$CuO$_{4}$ using resonant inelastic x-ray scattering in hard x-ray regime. We have observed charge excitations at the energy transfer of 1 eV with the momentum transfer corresponding to the charge stripe spatial period both for the diagonal (nikelate) and parallel (cuprates) stripes. These new excitations can be interpreted as a collective stripe excitation or charge excitonic mode to a stripe-related in-gap state.

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S. Wakimoto, H. Kimura, K. Ishii, K. Ikeuchi, T. Adachi, M. Fujita, K. Kakurai, Y. Koike, J. Mizuki, Y. Noda, A. H. Said, Y. Shvyd'ko, K. Yamada. 2008-06-20. Charge excitations associated with charge stripe order in the 214-type nickelate and superconducting cuprate. https://doi.org/10.1103/physrevlett.102.157001

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