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arXiv · 2505.11156

Simultaneous probes of pseudogap and disorder by hard x-ray photoemission applied for a candidate thermoelectric Al-Pd-Ru quasicrystal

N. U. Sakamoto·G. Nozue·H. Fujiwara·Y. Torii·M. Sakaguchi·T. D. Nakamura·T. Kiss·H. Sugawara·S. Tanaka·Y. Iwasaki·Y. Niwa·A. Ishikawa·T. D. Yamamoto·R. Tamura·A. Yasui·A. Sekiyama
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Abstract

The bulk electronic structure of Al-Pd-Ru quasicrystal (QC) have been investigated by hard X-ray photoemission spectroscopy (HAXPES). We have found an intrinsic pseudogap structure in which the spectral weight in the vicinity of the Fermi level (E_F) is remarkably suppressed at any photon energy. The valence-band HAXPES spectra and the asymmetry of the core-level peaks indicate a contribution of the Al sites to the electronic structure in the vicinity of E_F with less contributions from the Pd and Ru sites. The disorder effects are found in the core-level lineshapes of the Al-Pd-Ru QC, of which the widths are much broader than those of the other reference crystalline solids with less disorder.

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N. U. Sakamoto, G. Nozue, H. Fujiwara, Y. Torii, M. Sakaguchi, T. D. Nakamura, T. Kiss, H. Sugawara, S. Tanaka, Y. Iwasaki, Y. Niwa, A. Ishikawa, T. D. Yamamoto, R. Tamura, A. Yasui, A. Sekiyama. 2025-05-16. Simultaneous probes of pseudogap and disorder by hard x-ray photoemission applied for a candidate thermoelectric Al-Pd-Ru quasicrystal. https://arxiv.org/abs/2505.11156

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