Efficient Integrated Graphene Photonics in the Visible and Near‐IR. Issue 5 (2nd August 2017)

• Record Type: Journal Article
• Authors: Chang, PoHan; Lin, Charles; Helmy, Amr. S.
• Is Part Of: Laser & photonics reviews. Volume 11:Issue 5(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-08-02
• Subjects: metamaterial -- graphene photonics -- integrated optics -- 2D material; Lasers -- Periodicals; Photonics -- Periodicals; Lasers -- Périodiques; Photonique -- Périodiques; 621.36
• DOI: 10.1002/lpor.201700003
• Languages: English
• ISSNs: 1863-8880

Abstract

Abstract : The paper presents a novel guided wave approach utilizing metamaterial to overcome the limited light matter interaction of graphene devices in the near‐IR and visible regimes, where graphene plasmonics are not tenable. By rigorously examining the waveguide dispersion, the metamaterial approach can deliver significant leaps in device performance by optimizing the modal field that overlaps with graphene monolayer. This work elucidates a new avenue in the guided wave setting that unlocks the potential graphene holds in these important wavelength regimes. Abstract: Graphene photonics has emerged as a promising platform for providing desirable optical functionality. However, graphene's monolayer‐scale thickness fundamentally restricts the available light matter interaction, posing a critical design challenge for integrated devices, particularly in wavelength regimes where graphene plasmonics is untenable. While several plasmonic designs have been proposed to enhance graphene light interaction in these regimes, they suffer from substantial insertion loss due to metal absorption. Here we report a non‐resonant metamaterial‐based waveguide platform to overcome the design bottleneck associated with graphene device. Such metamaterial structure enables low insertion loss even though metal is being utilized. By examining waveguide dispersion characteristics via closed‐form analysis, it is demonstrated that the metamaterial approach can provide optimized optical field that overlaps with the graphene monolayer. This enables graphene‐based integrated components with superior optical performance. Specifically, the metamaterial‐assisted graphene modulator can provide 5‐fold improvement in extinction ratio compared to Si nanowire, while reducing insertion loss by one order magnitude compared to plasmonic structures. Such a waveguide configuration thus allows one to maximize the optical potential that graphene holds in the telecom and visible regimes.