Numerical Analysis of Deep sub-wavelength integrated plasmonic devices based on Semiconductor-Insulator-Metal strip waveguides

Abstract

We report the first study of nanoscale integrated photonic devices constructed with semiconductor-insulator-metal strip (SIMS) waveguides for use at telecom wavelengths. These waveguides support hybrid plasmonic modes transmitting through a 5-nm thick insulating region with a normalized intensity of 200-300 μm(-2). Their fundamental mode, unique transmission and dispersion properties are consistent with photonic devices for guiding and routing of signals in communication applications. It has been demonstrated using Finite Element Methods (FEM) that the high performance SIMS waveguide can be used to fabricate deep sub-wavelength integrated plasmonic devices such as directional couplers with the ultra short coupling lengths, sharply bent waveguides, and ring resonators having a functional size of ≈1 µm and with low insertion losses and nearly zero radiation losses.

Design of a Low Loss Silicon Based Hybrid Dielectric-Loaded Plasmonic Waveguide and a Compact High Performance Optical Resonator

“…Among varieties of SPPWGs, the hybrid dielectric-loaded (DL) SPPWG combines the advantages of hybrid SPPWG [9][10][11] and DL SPPWG [12]: Long propagation length, relatively small mode area, and nanometer dimension of SPPWG [13][14][15]. The hybrid DL SPPWG using silicon (Si) dielectric (Si-based hybrid DL SPPWG, SiHDLW) [7,8,10,13,14,[16][17][18], which has been shown to yield strong field confinement [8,10,13,17,18], is a particularly attractive candidate for plasmonic devices because the waveguide is easier to fabricate with conventional nano/micro techniques [7]. In addition, SiHDLW optical devices adopting Silicon-on-Insulator (SOI) substrate, such as splitters [7], couplers [7,19], and modulators [20] have also been demonstrated.…”

“…In addition, SiHDLW optical devices adopting Silicon-on-Insulator (SOI) substrate, such as splitters [7], couplers [7,19], and modulators [20] have also been demonstrated. Furthermore, the SiHDLW shows two common structures of top metal SiHDLW (TM-SiHDLW) [7,8,16,17,21] and bottom metal SiHDLW (BM-SiHDLW) [10,14,22]. The TM-SiHDLW shows a more promising potential than the BM-SiHDLW because of its flexibility to integrate with nanophotonic circuits [18].…”

“…The TM-SiHDLW shows a more promising potential than the BM-SiHDLW because of its flexibility to integrate with nanophotonic circuits [18]. For the SiHDLWs, a mode area as low as 0.0007 µm 2 -0.018 µm 2 has been achieved but with a propagation length limited in the range of 20 µm-100 µm [8,[16][17][18]. A special design running at a high order SPP waveguide mode have been proposed to give a propagation length as high as 1 mm but with a large mode area of 0.15 µm 2 , as expected [18].…”

Confinement and optical properties of the plasmonic inverse-rib waveguide

“…Currently, hybrid plasmonic waveguide proposals are emerging, using a low-index dielectric between a metal and a waveguiding higher index dielectric [6][7][8][9]. They often assume "square" geometries that are derived from simplified processing considerations, such as a preference for vertical etching and silicon-oriented applications.…”

Experimental demonstration of low-loss optical waveguiding at deep sub-wavelength scales

“…A hybrid plasmon polariton (HPP) concept has been proposed to overcome this challenge 11,26,27 . This approach uses a high dielectric constant semiconductor strip separated from a metal surface by a nanoscale low dielectric constant gap.…”