  We report on the design and simulation of strip-loaded nanophotonic
interfaces aimed at improving resonant coupling and photon routing efficiency.
In our design, the guided mode is confined within a plane by a high-index thin
film and is loosely confined laterally by a lower index strip. Using a hydrogen
silsesquioxane (HSQ) strip, titanium dioxide core, and silicon dioxide
substrate, we optimise the waveguide dimensions for maximum lateral confinement
of light. Specifically, we propose a polymer-based Bragg grating cavity and
ring resonator that achieve near-optimal mode volumes and high Q-factors. Our
simulations suggest that a cavity with a mode volume of V_{\text{eff}} \approx
7.0 \left(\frac{\lambda}{n}\right)^3 and a Q-factor of 7000 can produce photons
with 97% indistinguishability at 4K. Additionally, we investigate directional
couplers for efficient photon routing, comparing photonic and plasmonic
material structures. While pure photonic structures demonstrate lower loss and
improved quality factors, they face practical limitations in terms of bending
radius. Conversely, plasmonic structures offer shorter bending radii but higher
propagation losses. This research lays the groundwork for future nanophotonic
designs, aiming to enhance photon generation and routing capabilities for
quantum optical applications.
