Research On Key Techniques Of All-optical Logic Gates

With the rapid development of the Internet and multimedia technologies,the data traffic of the Internet has increased explosively.The currently available bandwidth is far from meeting the needs of users.Therefore,the communication speed must be increased to maintain and expand the application of the Internet.In the existing communication network,the response speed of each electronic device has approached the limit of the electronic speed,and there is unnecessary conversion of O-E-O at various nodes responsible for information exchange.Although in the past few decades,with the development of microelectronics innovation,electronic devices and integrated circuits can meet the increasing demand for high-speed data transmission and processing,in the near future,traditional electronic devices will hit the bottleneck that limits their speed.In order to overcome the bottleneck of the current communication system,optical signal processing technology is evolving and the technology is expected to overcome the limit of speed and complexity brought by the traditional electric signal processing technology.The optical logic gate as a key component of optical signal processing technology has also been extensively studied.This paper mainly focuses on this hot issue and conducts in-depth research and analysis on high-speed,reconfigurable all-optical logic gate technology.The concrete research contents are as follows:(1)All-optical logic gate scheme realized by eight different types of two major categories is studied,and the comparison and analysis of each scheme is carried out.Based on the previous research work of the research group,an all-optical logic gate based on polarization modulation is proposed.The optical logic gate has the advantages of simple structure,high speed and reconfigurable.(2)A mathematical model of optical logic gate based on polarization modulation is established.On the one hand,the realization principle of the six basic logical relations is explained from the azimuth coordinate system.On the other hand,a unique Poincare is proposed and the principle of the logic gate is explained more intuitively in the unique Poincare.(3)The performance evaluation system of optical logic gate is established,and the performance of optical logic gate system is measured from two aspects of extinction ratio and Q factor respectively.The factors that affect the performance of optical logic gates are analyzed theoretically.At the same time,a simulation platform is set up and the effects of extinction ratio,loss,laser output power and polarization rotation angle on the system performance are analyzed.Finally,an experimental platform was built and the feasibility of the six optical logic operations were verified experimentally.