The Research Of All Optical Switch Controlled By Light

With the explosive increase of information in modern society, the optical fiber transmission systems are required to have the properties of higher speed and higher capacity. According to the development of optical communication technology and the application of DWDM system, all-optical switching has become a tendency of optical network development. To achieve the all-optical switching, it must depend on the development of optical switch and other related devices.The speed of traditional MEMS optical switch, heat optical switch, liquid crystal optical switch is several ms, which cannot catch up with the demand of optical switching. The electronic-optical switch is sensitive to polarization, so it is hard to satisfy the demand of optical switching. But the speed of photon induced optical switch can be several ps, and it is independent to polarization. With the optimization of its structure, its performance can be applicable. So the study of photon induced optical switch has science research value and application value.This paper built up an analysis model of the refractive index change of semiconductors induced by photo-induced carrier. Using this model, we can study on the inherence mechanism of all-optical switch deeply. This analysis model has discussed the different conditions under the steady and transient photon injecting. The experiment results have also proved the correctness of the analysis model.Based on the foundation of research made by other researchers, the paper designed and optimized the all optical switches (such as Y branching TIR all optical switch, X junction all optical switch, etc.) by beam propagate method (BPM). And it had acquired good simulation design results. This paper fabricated the optical waveguide devices by wet etching method (A technology used in microelectronic fabrication).This paper built up a testing system which is convenient and practical. Using infrared camera to collect the near-field distributing of optical switch output and analyzing the data by Gaussian curve fit method, the device performance parameters such as the extinction ratio and cross talk were measured by the testing system. Thistesting system also used laser diode with fiber tail to simplify the operation of photon injection.Up to the present, this paper has fabricated 1x2 asymmetric Y-braching TIR (total internal reflection) all-optical switch. From the primary measure, we have got the result that the extinction ratio of "bar cannel" is 8dB and the extinction ratio of " cross channel" is more than 18dB. We have also got the primary testing results on coupling structure and M-Z structure all-optical switches. The precise measurement of the device performance parameters will be finished after the device is packaged.