Plasmonic structure integrated single-photon detectors optimized to maximize polarization contrast

Numerical optimization was performed via COMSOL multiphysics to maximize the polarization contrast of superconducting nanowire single photon detectors (SNSPDs). SNSPDs were integrated with four different types of 1D periodic plasmonic structures capable of mediating p-polarized photon selectivity to the niobium-nitride superconducting nanowire pattern. Optimization with two different criteria regarding the maximal tilting resulted in wavelength-scaled periodic integrated structures, which have different geometrical parameters, and exhibit different polar angle dependent optical responses and dispersion characteristics, as well as accompanying near-field phenomena at the extrema. Polarization contrast of 6.4·10^2 and 3.3·10^2/6.9·10^11 and 1.4·10^11/1.8·10^13 and 7.9·10^12/1.9·10^3 and 1.2·10^5 can be achieved in nanocavity-/nanocavity-deflector-/nanocavity-double-deflector-/nanocavity-trench-array-integrated P-SNSPDs optimized with 85° and 80° criterion, regarding the maximal tilting