Open AccessMultifunctional optoelectronic device based on graphene-coupled silicon photonic crystal cavities
Author(s) -
Xiaoxu Chen,
Fangjie Wang,
Qiongqiong Gu,
Jinghui Yang,
Mingbin Yu,
DimLee Kwong,
Chee Wei Wong,
Huajun Yang,
Hao Zhou,
Shouhuan Zhou
Publication year - 2021
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.421596
Subject(s) - optoelectronics , materials science , responsivity , graphene , photodetector , optical switch , bistability , silicon photonics , modulation (music) , optical modulator , photonic crystal , silicon , optics , photocurrent , phase modulation , nanotechnology , physics , acoustics , phase noise
We present a hybrid device based on graphene-coupled silicon (Si) photonic crystal (PhC) cavities, featuring triple light detection, modulation, and switching. Through depositing single-layer graphene onto the PhC cavity, the light-graphene interaction can be enhanced greatly, which enables significant detection and modulation of the resonant wavelength. The device is designed to generate a photocurrent directly by the photovoltaic effect and has an external responsivity of ∼14 mA/W at 1530.8 nm (on resonance), which is about 10 times higher than that off-resonance. Based on the thermo-optical effect of silicon and graphene, the device is also demonstrated in electro-optical and all-optical modulation. Also, due to the high-quality (Q) factor of the resonate cavity, the device can implement low threshold optical bistable switching, and it promises a fast response speed, with a rise (fall) time of ∼0.4 μs (∼0.5 μs) in the all-optical switch and a rise (fall) time of ∼0.5 μs (∼0.5 μs) in the electro-optical hybrid switch. The multifunctional photodetector, modulator, and optical bistable switch are achieved in a single device, which greatly reduces the photonic overhead and provides potential applications for future integrated optoelectronics.