Photorefractive trimming of Ti in-diffused waveguides for high performance lithium niobate photonic integrated circuits

Photorefractive Photonics 2017

Tronev, A.^1,2 ; Parfenov, M.^3 ; Dolbik, D.^3 ; Agruzov, P.^1 ; Ilichev, I.^1 ; Shamray, A.^1,2,3

Ioffe Institute, Polytekhnicheskaya 26, St. Petersburg

194021, Russia^1

ITMO University, Kronverksky av. 49, St. Petersburg

197101, Russia^2

Peter the Great Saint-Petersburg Polytechnic University, Polytekhnicheskaya 29, St. Petersburg

195251, Russia^3

关键词: Change of refractive index;    Diffused waveguides;    Efficient control;    Extinction ratios;    High extinction ratios;    Optimal conditions;    Photonic integrated circuits;    Photorefractive effects;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/867/1/012015/pdf
DOI  :  10.1088/1742-6596/867/1/012015

来源: IOP

【 摘 要 】

A local micro-size change of refractive index due to photorefractive effect was effectively used for precise adjustment of the splitting ratio of waveguide optical splitters. The optimal conditions for efficient control of a splitting ratio for two basic configurations (X-coupler and Y-branch) were found. To demonstrate the efficiency of the proposed method the adjustment of extinction ratio of Mach-Zehnder integrated optical modulator was performed. The increase of 17 dB (from 30 to 47 dB) was obtained. The results are very promising for fabrication high extinction ratio modulators for quantum key distribution, precise sensing, high fidelity signal processing and others.