Controlled hybridization of gaas-based vertically coupled hybrid plasmonic waveguide for low-loss nanoscale optical confinement

Abstract

Plasmonic waveguiding stands at the forefront of nanophotonic innovation, offering immense potential for the development of compact and efficient nanophotonic devices. Despite its promise, this field has faced challenges, particularly in managing significant propagation losses that hinder device performance and efficiency. Addressing this critical barrier, we present an engineered GaAs-based vertically coupled hybrid plasmonic waveguide (VCHPW) that leverages controlled hybridization to achieve ultra-low-loss nanoscale optical confinement. Our innovative vertical coupling design enhances the interaction between plasmonic and dielectric layers, leading to superior mode confinement and substantially reduced propagation losses. The state-of-the-art design achieves remarkable performance, with ultra-low propagation losses of 0.004 dB/μm over a propagation length of 790 μm at a wavelength of 1.35 μm, and 0.0007 dB/μm over a propagation length of 5330 μm at a wavelength of 1.65 μm. Furthermore, the device exhibits a figure of merit ranging from 2280 to 5700. In comparison to conventional GaAs-based hybrid plasmonic waveguides, our proposed device demonstrates a reduction in loss by a factor of over 100. Additionally, it shows a significantly enhanced figure of merit and extended propagation length, marking an advancement in plasmonic waveguide performance. This meticulous engineering ensures that our VCHPW not only surpasses traditional hybrid plasmonic waveguides in terms of efficiency and confinement but also offers scalability and integration potential. These attributes are essential for future high-performance nanophotonic systems for communication and sensing technologies.