Study Of Electrodeflector Based On Potassium Tantalate Niobate

With the coming of the age of information, transporting and treating hugeamount of information with high efficiency is becoming a serious question. Withrespect to this, the concept of optical-network and optical-communicationtechnology has been put forward. At the same time, the fabrication of opticaldevices with high stability, high integration and tunability has been the urgentaffair.Because laser has highly directionality, the steering of beam propagationdirection appears to be so important. As with most beam deflectors being based onmachanical components, acousto-optic materials, liquid crystals and so on. Theircraftmanship is complicated, responding time is long, the repeatability is bad andthe cost is high. However, the paraelectric quadratic electro-optic material,potassium tantalate niobate (KTN), has large secondary electro-optic coefficientsand the response speed has reached a nanosecond level. We will study the growthand good peformance of electro-optic effect of the KTN single crystal, basing onwhich we make a electric-field-controlled beam deflector, and study the propertiesof it.Firstly, we explored the properties of the potassium tantalate niobate crystals.With the top seeded solution growth method, we experienced batching, presintering,ingredients melting, shrinkage, shouldering, straight-pulling and cooling. Eachprocess concerns the quality of the final crystal. The as-grown crystal has beenprocessed into Crystal1and Crystal2. We explored dielectric constants changingwith the temperature.Secondly, we studied the potassium tantalate niobate crystals’ electricproperties. The quadric electro-optic coefficients were measured by an dynamictwo-beam Mach-Zehnder system. We got the conclusion that the potassium tantalateniobate crystals have excellent voltage controlled photorefractive property, whichmakes it attractive in fabrication of good electro-optic devices.Finally, with theoretical deduction and experimental verification，we discussthe principal of our electro-field-controlled beam deflector. Then, we discuss theperformance of the device with the changing of external electric field and thepolarization of incident light. And we put forward the one-dimensional andtwo-dimensional electric-field-controlled optical splitting systems, which has beenstudied in theory and experiment.This study will contribute to the development of novel electro-optic device, which promotes the development of the good electric-field-controlled beamdeflecting.