Photonics Research

Proposal and demonstration of a controllable Q factor in directly coupled microring resonators for optical buffering applications

Ying Zhang, Qiang Liu, Chenyang Mei, Desheng Zeng, Qingzhong Huang, Xinliang Zhang

Published Aug 17, 2021• 18 citations

Abstract

Optical resonators with controllable Q factors are key components in many areas of optical physics and engineering. We propose and investigate a Q -factor controllable system composed of two directly coupled microring resonators, one of which is tunable and coupled to dual waveguides. By shifting the resonance of the controllable microring, the Q factor of the system as well as the other microring changes significantly. We have demonstrated wide-range controllable Q factors based on this structure in silicon-on-insulator, for example. The influences of spectral detuning and coupling strength between two resonators on the variation of Q factors are studied in detail experimentally. Then, we explore its applications in optical buffering. Tunable fast-to-slow/slow-to-fast light has been carried out by switching the system between the high- Q state and low- Q state. Moreover, optical pulse capture and release are also achievable using this structure with dynamic tuning, and the photon storage properties are investigated. The proposed Q -factor tunable system is simple, flexible, and realizable in various integrated photonic platforms, allowing for potential applications in on-chip optical communications and quantum information processing.

DOI: 10.1364/prj.434151

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