The influence of a local refractive index change on the splitting ratio of an integrated optical Y-branch on lithium niobate substrate

Abstract

The power splitting ratio tuning of a lithium niobate integrated optical Y -branch caused by a local refractive index change was investigated. Controllable local refractive index change was produced by photorefractive effect at external laser irradiation. The dependences of the splitting ratio change on the position of the local refractive index change had interferometric nature. The effect could be used for precise tuning of the Y -branch splitting ratio.