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981.
T. Kageyama T. Hasegawa T. Koida M. Ohtani T. Fukumura M. Kawasaki H. Koinuma 《Applied Physics A: Materials Science & Processing》2001,72(8):S273-S276
We performed scanning SQUID microscopic measurements on composition-spread La1-xSrxMnO3 films deposited on various substrates. In thick films, the obtained local magnetic property as a function of x reproduces the bulk phase diagram well. In thin films (40 nm), we found that the phase boundaries significantly shifted depending on substrate materials. The stability of magnetic phases is discussed in term of the local strain associated with the lattice mismatch between film and substrate. 相似文献
982.
Akihiro Yamamoto Chih-Che Kuo Kei Sunouchi Satoshi Wada Ichirou Yamaguchi Hideo Tashiro 《Optical Review》2001,8(1):59-63
We developed a high speed and high resolution surface shape measurement system based on wavelength scanning interferometry with an electronically tuned Ti:sapphire laser. This laser emits pulses and the wavelength of each pulse can be tuned arbitrarily within 680 nm and 1056 nm. We also designed a high speed multiport CCD camera as a detector. This camera is synchronized with wavelength scanning of the laser at the frequency of 250 Hz. We could measure the object shape with a height resolution of 3.05 μm at the tuning range from 740.0 nm to 842.3 nm. By simple parabolic curve fitting to the Fourier peak of interference signals from each CCD pixel, the height resolution has been improved to the order of submicrometers. 相似文献
983.
Hiroyasu Kondo Kazuaki Inohara Yuki Taniguchi Junko Nakahata Tetsuya Homma Hideo Takahashi 《Optical Review》2001,8(5):323-325
A thermo-optic switch in a thin-film optical waveguide was investigated. Fluorinated silicon oxide (SiOF) and organic spin-on-glass (SOG) films were used as core-layer and clad-layer, respectively, in the waveguide structure. The SiOF films were formed at 23#x00B0;C by a liquid-phase deposition (LPD) technique using a supersaturated hydrofluosilicic acid (H2SiF6) aqueous solution. Thermal coefficients of the refractive indices for LPD-SiOF and organic SOG films formed on silicon (Si) substrates were #x2212;4.0 #x00D7; 10#x2212;6/#x00B0;C, #x2212;60 #x00D7; 10#x2212;6/#x00B0;C at the wavelength of 632.8 nm, respectively. A high extinction ratio of 15 dB was obtained for this switch at the applied voltage of 12.8 V. 相似文献
984.
Hideo Hasegawa 《Foundations of Physics》2000,30(12):2061-2078
The mean-field theory with the use of the slave-boson functional method has been generalized to take account of the spin- and/or orbital-ordered state in the doubly degenerate Hubbard model. Numerical calculations are presented of the antiferromagnetic orbital-ordered state in the half-filled simple-cubic model. The orbital order in the present theory is much reduced compared with that in the Hartree–Fock approximation because of the large orbital fluctuations. From a comparison of the ground-state energy, the antiferromagnetic orbital state is shown to be unstable against the antiferromagnetic spin state, although the situation becomes reversed when the exchange interaction is negative. 相似文献
985.
S. Ajimura H. Bhang H. Ejiri T. Hasegawa O. Hashimoto M. Ishikawa K. Ikeda Y. Kim T. Kishimoto K. Maeda K. Manabe T. Nagae T. Nakano H. Noumi A. Okusu H. Park M. Sekimoto T. Shibata N. Shinkai T. Takahashi Y. Tanaka M. Youn 《Nuclear Physics A》2000,670(1-4):285-288
We measured the asymmetric weak decay of the polarized Λ5He hypernuclei. The polarization was derived by the observed asymmetry of the mesonic decay pions for the first time. The asymmetry parameter of the nonmesonic decay has been evaluated using the obtained polarization and the asymmetry of the decay protons. The positive asymmetry parameter contradicts theoretical prediction based on meson exchange model. The present data indicates the limitation of the model in ΛN weak interaction, in particular short range phenomena such the nonmesonic decay of hypernuclei. 相似文献
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