All-optical control of light on a graphene-on-silicon nitride chip using thermo-optic effect.

ABSTRACT: All-optical signal processing avoids the conversion between optical signals and electronic signals and thus has the potential to achieve a power efficient photonic system. Micro-scale all-optical devices for light manipulation are the key components in the all-optical signal processing and have been built on the semiconductor platforms (e.g., silicon and III-V semiconductors). However, the two-photon absorption (TPA) effect and the free-carrier absorption (FCA) effect in these platforms deteriorate the power handling and limit the capability to realize complex functions. Instead, silicon nitride (Si3N4) provides a possibility to realize all-optical large-scale integrated circuits due to its insulator nature without TPA and FCA. In this work, we investigate the physical dynamics of all-optical control on a graphene-on-Si3N4 chip based on thermo-optic effect. In the experimental demonstration, a switching response time constant of 253.0?ns at a switching energy of ~50?nJ is obtained with a device dimension of 60??m?×?60??m, corresponding to a figure of merit (FOM) of 3.0?nJ?mm. Detailed coupled-mode theory based analysis on the thermo-optic effect of the device has been performed.

SUBMITTER: Qiu C 

PROVIDER: S-EPMC5719060 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature