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981.
Kamiya T. Tsuchiya M. Miyamoto M. Lee J. Tanaka T. Sasaki S. 《Optical and Quantum Electronics》2000,32(4-5):443-452
Ultrashort laser pulses offer new jump in information and communication technology. Especially semiconductor laser based ultrafast photonic devices and systems are promising. We review our new approaches for femtosecond pulse generation, and thin film technology for broad band semiconductor optical amplifiers. 相似文献
982.
Matteo A.M. Tallone L. Boidi C. Cognolato L. Pozzi F. 《Optical and Quantum Electronics》2000,32(6-8):981-990
We present a semi-analytical modeling suitable for the investigation of the spectral characteristics of UV-waveguide Bragg gratings (UV-WBGs) having arbitrary apodization function and extending both in the film layer and in the overlayer. The modeling is based on a proper combination of coupled mode theory and transfer matrix formalism and provides a powerful tool for designing and simulation of complex UV-grating based structures. The results of a detailed investigation of UV-WBGs in doped silica based channel optical waveguides are presented and critical issues for upgrading the performances of related device are discussed. Validation of the modeling is provided by means of an extensive comparison between theoretical and experimental results relevant to UV-WBGs realized in phosphorous (P)- and boron (B)-doped silica based waveguides. 相似文献
983.
We have solved a self-consistent problem on interaction of two dipole atoms located at an arbitrary distance from each other
with the field of a quasiresonance light wave, whose intensity is sufficient for the system to manifest nonlinear properties.
The atoms are considered as two-level systems described by means of Bloch optical equations, while the field inside of the
system includes both Coulomb and retarded parts. We consider a situation where atoms are identical and the distance between
them is much smaller than the length of an outer light wave. The distribution of an electric field both inside of a small
object and outside of it is found numerically. It is shown that the amplitude of the electric field in a wave zone depends
substantially on the frequency of the external field and interatomic distance, while the field distribution differs from the
field pattern of an electric dipole. At definite values of the external field intensity an optical multistability is a feature
of the system under investigation. We have elucidated the conditions under which the multistability is manifested in the present
system. The results obtained are considered as the near-field effect in the optics of small objects, which makes it possible
to investigate the structure of small objects by means of optical radiation.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 375–378, May–June, 2000.
The present work was supported by the Russian Foundation for Fundamental Research (grant 98-02-16035) and by a grant from
the Federal Purpose-Oriented Program “Integration.” 相似文献
984.
XiangLin Yang YangJing Wen Ming Xu 《International Journal of Infrared and Millimeter Waves》2000,21(9):1495-1502
The control scheme of long distance optical transmission is treated based on conception of mode-locked Laser cavity in this paper. The general mode-locking equation of fiber ring soliton Laser is first constructed, then we give the general perturbed nonlinear schrödinger equation, and finally the transmission and control equations of optical soliton communication systems with various different configurations, respectively, are obtained. 相似文献
985.
D. Dymitrov 《Optics & Laser Technology》1986,18(3)
A simple method is described for defining the size and location of the slit in a rainbow holography optical system in order to guarantee the optimal observation conditions of the reconstructed image. A brief explanation of the basic principles of rainbow holography is given and the projection of viewing slits and pseudoscopic, or orthoscopic, images is considered. An application of the method for afocal systems used in rainbow holography is presented. 相似文献
986.
987.
本文给出有序混合光束结构和多程光学系统的具体考虑,并指出它们在多波长高激发态激光光谱学研究和其它领域中的意义. 相似文献
988.
A new method to remove water adsorbed on flouride glass preforms is reported. This method, using NF3 plasma, can remove surface water on fluoride glasses 相似文献
989.
本文用卢瑟福背散射和光吸收技术研究了高剂量Ag离子注入SiO_2玻璃以及退火后的状况.吸收光谱测量表明,注入的Ag离子聚集形成了胶态粒子,其等离子共振峰的极大值在400nm处.运用米(Mie)理论和德拜(Doyle)方法,根据测得的等离子共振峰的光宽度,估算出Ag胶态粒子的半径约为18(?). 相似文献
990.