Research On Logic Device Based On Micro-ring Resonator

With the arrival of the global information era,communication technology with huge capacity,high rate of network is the inevitable trend of the development of communication technology.The integrated optical device has the advantages of miniaturization,modularization,integrated,become the future development trend of optical communication devices.Micro-ring resonator has the advantages of multiple functions,small size,good wavelength selectivity,has been widely applied in the field of optical communication.The main purpose of this thesis is to investigate a novel optical processing approach called ‘directed logic'.This concept was firstly proposed in 2007 by Prof.James Hardy from the U.S.and Prof.Joseph Shamir from Israel.The underlying idea of their proposal is to use logical operands to control the switch state in the optical switch networks to control the propagation direction of the light,and the final operation results are obtained in the form of light at the optical output ports at last.Directed logic employs optical switch networks to control the propagation of the light to achieve logic operations,which has the following advantages: one,the control signal of directed logic is electronics,and the operation signal is optics,therefore,directed logic reasonably utilizes the strengths of both optics and electronics while avoiding their weaknesses;two,all the operands act on their corresponding switches simultaneously.This is different from the traditional electrical logic circuit where the inputs that determine the states of the elements must pass through the preceding elements in the circuit;three,it relies on the propagation of light to carry out the calculation,making it inherently possess high-bandwidth and low-delay features.In this thesis,we design and implement a kind of multi-function electro-optic logic gate based on the microring resonator.The main research contents are as follows:(1)The working principle of the microring resonator is analyzed,and the normalized output spectrum of through and download port is deduced.The characterization parameters of the microring resonator are given.(2)The principle of optical directed logic is explained,and the working mode of the device is discussed.Refractive index modulation mechanism of the polymer is derived,and the formula of refractive index with modulation voltage is obtained.(3)By using the microring resonator as optical waveguide device,multifunctional optical logic gate is designed and realized.The principle is based on the mechanism of refractive index modulation."AND/NOT","OR /NOR","XOR/ XNOR logic operation can be achieved by changing different ports of the logic inputs,respectively.The working wavelength is determined by the static test and dynamic simulation further verifies the designed device logic function.(4)By using the time domain model of the microring resonator and the number of the resonantring,the limit working speed of the device is calculated.The ultimate operating speed of the device by formula is consistent with the numerical simulation results,which is about 6Gb/s.