2026-03-08T04:12:13Z https://jaxa.repo.nii.ac.jp/oai

oai:jaxa.repo.nii.ac.jp:00034240 2023-06-20T23:46:24Z 1887:1890 1896:1898:1899:1908

酸化タングステンの強電性の研究 : I. Curie點の存在 Abstract: Study on the Ferroelectricity of Tungsten Oxide. : I, Existence of the Curie Point. 澤田, 正三 安藤, 林次郎 Sawada, Shozo Ando, Rinjiro The domain structure of single crystals of tungsten oxide and the influence of electric field on it, were investigated using a polarized-light microscope from room temperature up to 900℃. It was found that the domain patterns vanish at. about 710℃ above which temperature the birefringence is no more discernible, and that a electric field has a remarkable effect on the domain structure just below this temperature. The thermal expansion and the specific heat of this substance were measured, though indirectly, using ceramic, samples and an anomaly was observed distinctly in each case near 710℃. Furthermore, the area of hysteresis loop decreases gradually with increasing temperature and finally the hysteresis loop becomes linear near 700℃. These results seem to, lead us to a conclusion that tungsten oxide has a spontaneous polarization, perhaps m the direction of b-axis vanishing at about 710℃. 資料番号: SA1511497000 東京大学理工学研究所 1951-03-16 jpn departmental bulletin paper https://jaxa.repo.nii.ac.jp/records/34240 0371-6090 AN00162611 東京大學理工學研究所報告 4 9/10 228 231 https://jaxa.repo.nii.ac.jp/record/34240/files/SA1511497.pdf application/pdf 422.4 kB 2020-01-24