Ultra-compact and ultra-broadband hybrid plasmonic-photonic vertical coupler with high coupling efficiency, directivity, and polarisation extinction ratio

Pezeshki, Hamed; Wright, Amanda J.; Larkins, Eric C.

Abstract

An ultra-compact, ultra-broadband vertical coupler for dense photonic integrated circuits is reported with a 1.07×0.62μm2 wavelength-scale footprint. This hybrid plasmonic-photonic coupler uses a unique two-plane plasmonic nanoantenna array on a silicon-on-insulator waveguide. The in- and out-of-plane interference of the multipole moments and dual-feed nanoantennas results in efficient, unidirectional coupling. Finite-element simulations show that, for a 0.8μm diameter Gaussian beam, the maximum coupling efficiency (CE) is −3.4dB across the telecommunication C-, L- and U-bands with a 3-dB bandwidth of 230nm. The CE is>9dB higher than recently reported ultra-compact plasmonic couplers. The maximum directivity and polarisation extinction ratio across the C- to U-bands are 9.2 and 24.1dB, respectively. Finally, as an out-coupler, it has a vertical directivity of >8.5dB, enabling its use for vertical optical interconnects between two vertically separated circuits.

Citation

Pezeshki, H., Wright, A. J., & Larkins, E. C. (2022). Ultra-compact and ultra-broadband hybrid plasmonic-photonic vertical coupler with high coupling efficiency, directivity, and polarisation extinction ratio. IET Optoelectronics, 16(3), 124-132. https://doi.org/10.1049/ote2.12063

• Journal Article Type: Article
• Acceptance Date: Dec 3, 2021
• Online Publication Date: Jan 4, 2022
• Publication Date: 2022-06
• Deposit Date: Jan 21, 2022
• Publicly Available Date: Jan 21, 2022
• Journal: IET Optoelectronics
• Electronic ISSN: 1751-8776
• Publisher: Institution of Engineering and Technology (IET)
• Peer Reviewed: Peer Reviewed
• Volume: 16
• Issue: 3
• Pages: 124-132
• DOI: https://doi.org/10.1049/ote2.12063
• Keywords: Electrical and Electronic Engineering; Atomic and Molecular Physics, and Optics
• Public URL: https://nottingham-repository.worktribe.com/output/7283295
• Publisher URL: https://ietresearch.onlinelibrary.wiley.com/doi/10.1049/ote2.12063