Investigation of optical properties of Ce3+-doped Gd2SiO5 crystal irradiated by a femtosecond laser

We report on the optical property changes for Ce3+-doped Gd2SiO5 crystal irradiated by a femtosecond (fs) laser. Absorption spectra showed that Ce-related color centers were formed in this crystal after an 800 nm fs laser irradiation. The annealing temperature-dependence of the refractive index and absorption intensity changes have been investigated. Furthermore, a new way of writing overlapped gratings inside the crystal by use of birefringence of fs laser beam in this crystal was proposed. (c) 2005 Elsevier B.V. All rights reserved.

The SPER and characteristics of Si1-yCy alloys

\Si1-yCy alloys with carbon composition of 0.5 at.% were successfully grown on n-Si(100) substrate by solid phase epitaxy recraystallization. The result was presented in this paper. With the help of the SiO2 capping layer, rather uniform carbon profile in amorphous Si layer was obtained by dual-energy implantation. Since ion-flow was small and implantation time was long enough, the emergency of beta-SiC was avoided and the dynamic annealing effect was depressed. The pre-amorphization of the Si substrate increased the fraction of the substitutions carbon and the two-step annealing reduced point defects. As a result, Si1-yCy alloys with high quality was recrystallized on Si substrate.

影响汉字手写体识别的静态特征与动态特征的研究

In this study, the recognition of handwritten Chinese characters is studied by analyzing their static and dynamic factors. The main results are as follows: 1) The static factors of handwritten Chinese characters that have significant effects on recognition are similarity with other handwritten characters, changes of relative positions of strokes and shape changes of strokes; 2) The methods of writing handwritten Chinese characters used by different calligraphers are significantly consistent; 3)The subjects are sensitive to dynamic information contained in the handwritten Chinese characters; 4)The dynamic factors that effect recognition of handwritten Chinese characters are changes in the number of strokes and changes in the direction of strokes; 5)Although both static and dynamic factors of handwritten Chinese characters have significant effects on the recognition of handwritten Chinese characters, the effect of static factors plays a major role and the effect of dynamic factor plays of secondary role.