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961.
Fabrication techniques of ultra-thin optical polarizing films using gold island films have been investigated for the near-infrared region. The polarizing films are fabricated by stretching the periodic multilayers consisting of gold island layers and glass layers. We have experimentally investigated the optimum fabricating conditions necessary to induce large optical anisotropy into the gold island layers and have formed submicrometer-thick polarizing films with an extinction ratio of ≥20 dB in a near-infrared region longer than 800 nm. These polarizing films could be useful micro-polarizers for fiber-embedded in-line optical devices, micro-optics, and hybrid integrated optics. 相似文献
962.
Jozef Kowalewski Lawrence Werbelow 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,128(2):144-148
General comments related to the impact of the antisymmetric component of the electronic shielding tensor in context of nuclear magnetic relaxation studies are given. It is argued that in most conceivable applications of high field NMR, the effects associated with the antisymmetric component will be negligible. However, in certain situations, this conventional wisdom may fail and, as an extreme example, it is demonstrated that for highly nonaxially symmetric shieldings, motional anisotropy may accentuate dramatically therelativeimportance of the antisymmetry. 相似文献
963.
F. Cayssol D. Ravelosona J. Wunderlich C. Chappert V. Mathet J. -P. Jamet J. Ferr 《Journal of magnetism and magnetic materials》2002,240(1-3):30-33
Extraordinary Hall effect was used to detect the propagation of a domain wall in magnetic devices patterned in sputter grown Pt/Co(1 nm)/Pt sandwiches with perpendicular easy magnetization axis. In such films, domain walls propagate as coherent 1D nano-object in a 2D medium with weak fluctuation energy density. In a patterned device, the competition between global wall energy and Zeeman energy strongly influences the wall propagation. 相似文献
964.
Time-resolved anisotropy measurements were performed using simple instrumentation with the aim to demonstrate the speed and ease of the experiment. Subsequent data analysis examples involved common, easily adaptable procedures. 相似文献
965.
Piotr Tekely Pascal Palmas Pierre Mutzenhardt 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,127(2):238-240
It is shown that the proton chemical-shift anisotropy of hydrate crystals affect dipolar powder pattern at 7.0 T. This may be clearly observed via an asymmetric envelope of dipolar spinning sidebands in magic-angle spinning proton spectra. 相似文献
966.
Thomas Vosegaard Hans J. Jakobsen 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,128(2):135-137
Accurate values for the27Al chemical shielding anisotropy (CSA) are reported for sapphire (α-Al2O3). The values (δσ= −17.3 ± 0.6 ppm, ησ= 0.03 ± 0.06) are obtained from single-crystal27Al NMR and appear to be the first convincing determination of an27Al CSA. 相似文献
967.
L. Smardz 《Journal of magnetism and magnetic materials》2002,240(1-3):273-276
NiO/Co and NiO/Ni80Fe20 bilayers were prepared at 293 onto SiO2(1 0 1)/Si(1 1 1) and glass substrates using UHV (5×10−10 mbar) RF/DC magnetron sputtering. Results on magnetic measurements showed that the exchange biasing and coercive fields are inversely proportional to the Co and Ni80Fe20 (Py) layer thickness down to 2 nm. A maximal RT coupling energy for the NiO–Co and NiO–Py interface was estimated as 0.04 and 0.03 mJ/m2 for the samples prepared onto SiO2(1 0 1)/Si(1 1 1) substrates. 相似文献
968.
Jingzhi Yin Guotong Du Shuping Liu Zongshun Liu Xinqiang Wang Zhengting Li Zongyou Yin Shuren Yang 《Optics & Laser Technology》2002,34(8):595-597
A polarization insensitive gain medium for optical amplifiers has been fabricated. The active layer is a structure with alternate tensile and compressive strain quantum wells. The waveguide is made into a taper with angled facets. In the experiment we found that the structure can suppress the lasing and decrease the polarization sensitivity. The gain imbalance between transverse electric and transverse magnetic gains is small, and 0.1 dB is obtained at a driving current of 100 mA. The full-width at half-maximum of amplified spontaneous emission is 40 nm within large current. 相似文献
969.
偏振光谱的测量及研究进展 总被引:14,自引:0,他引:14
本文介绍了几种测量物体偏振光谱的方法,评述了近年来各国科学家在军事目标、植物、海洋、不同材料面板等方面偏振测量取得的进展。 相似文献
970.
Mutasem A. Shehadeh Hussein M. Zbib Tomas Diaz de la Rubia 《International Journal of Plasticity》2005,21(12):2369-2390
Ultra short pulse shock wave propagation, plastic deformation and evolution of dislocations in copper single crystals with (0 0 1), (0 1 1) and (1 1 1) orientations are investigated using multiscale dislocation dynamics plasticity analyses. The effects of peak pressure, pulse duration, crystal anisotropy and the nonlinear elastic properties on the interaction between shock wave and dislocations are investigated. The results of our calculations show that the dislocation density has a power law dependence on pressure with a power of 1.70 and that the dislocation density is proportional to pulse duration and sensitive to crystal orientation. These results are in very good agreement with the analytical predications of Meyers et al. [Meyers, M.A., Gregori, F., Kad, B.K., Schneider, M.S., Kalantar, D.H., Remington, B.A., Ravichandran G., Boehly, T., Wark, J., 2003. Laser-induced shock compression of monocrystalline copper: characterization and analysis. Acta Materialia 51, 1211–1228] and the experimental results of Murr [Murr, L.E., 1981. Residual microstructure-mechanical property relationships in shock loaded metals and alloys. In: Meyers, M.A., Murr, L.E. (Eds.), Shock Waves and High Strain Rate Phenomena in Metals. Plenum, New York, pp. 607–673]. It is shown also that incorporating the effect of crystal anisotropy in the elastic properties results in orientation dependent wave speed and peak pressure. The relaxed configurations of dislocation microstructures show the formation of microbands coincident with the slip planes. 相似文献