Y
Yoichi Ishiwata
Researcher at Saga University
Publications - 22
Citations - 446
Yoichi Ishiwata is an academic researcher from Saga University. The author has contributed to research in topics: Quantum dot & Metal–insulator transition. The author has an hindex of 7, co-authored 22 publications receiving 400 citations. Previous affiliations of Yoichi Ishiwata include Saga Group & University of Tokyo.
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Giant negative thermal expansion in magnetic nanocrystals
TL;DR: It is proposed that the negative thermal expansion effect in CuO (which is four times larger than that observed in ZrW2O8) and MnF2 is a general property of nanoparticles in which there is strong coupling between magnetism and the crystal lattice.
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Synthesis and Application of Stable Copper Oxide Nanoparticle Suspensions for Nanoparticulate Film Fabrication
TL;DR: In this article, an alcothermal method was used for the preparation of colloidal suspensions of copper oxide (CuO) nanoparticles, which were stable for up to 1 month without stabilizers such as surfactants.
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Synthesis of Copper–Antimony-Sulfide Nanocrystals for Solution-Processed Solar Cells
Satoshi Suehiro,Keisuke Horita,Masayoshi Yuasa,Tooru Tanaka,Katsuhiko Fujita,Yoichi Ishiwata,Kengo Shimanoe,Tetsuya Kida +7 more
TL;DR: The synthesis of copper-antimony-sulfide NCs with different crystal phases with a diode-like current-voltage characteristic when coupled with an n-type CdS layer exhibited photovoltaic responses under simulated sunlight, demonstrating its applicability for use in solution-processed solar cells.
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High resolution soft X-ray absorption spectroscopy for the chemical state analysis of Mn
Jun Kawai,Yoshinobu Mizutani,Tetsuro Sugimura,Makoto Sai,Tohru Higuchi,Yoshihisa Harada,Yoichi Ishiwata,Akiko Fukushima,Masami Fujisawa,M. Watanabe,Kuniko Maeda,Shik Shin,Yohichi Gohshi +12 more
TL;DR: In this paper, the authors measured the X-ray absorption spectra of various manganese compounds using a synchrotron radiation facility, and very high-resolution spectra were obtained.
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Resonant Soft X-Ray Emission Spectroscopy of NiO across the Ni L2,3 Thresholds
Hirofumi Ishii,Yoichi Ishiwata,Ritsuko Eguchi,Yoshihisa Harada,M. Watanabe,Ashish Chainani,Shik Shin +6 more
TL;DR: In this paper, the electronic structure of NiO using resonant soft X-ray emission spectroscopy across Ni L 2,3 thresholds was studied and inelastic (Raman) features within 10 eV of the elastic peak energ...