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Periodontal diseases are prevalent worldwide and are linked to numerous other health conditions due to dysbiosis and chronic inflammatory state. Most periodontal diseases are caused by pathogenic bacteria that colonize dental tissues in the form of biofilm. Eradication of bacterial biofilms can be difficult to achieve due to the complex architecture of the teeth and gums which complicates the removal. Orthodontic wires and dental devices introduce additional hurdles to the adequate removal of biofilms by traditional methods since mechanical disruption via direct contact with toothbrush bristles, floss, and abrasive toothpaste is limited. Magnetically activated nanoparticles (NPs), specifically iron oxide nanoparticles (IONPs) that can be functionalized as antimicrobial particles and remotely controlled by magnetic fields, are of interest for oral biofilm eradication. We present data in multi-species bacterial cultures, established biofilms, human gingival keratinocytes, and human gingival fibroblast cells alone and in the presence of multispecies biofilm co-cultures to determine the safest, most efficacious IONP size ranges and treatment concentrations of active magnetic NPs for removal of dental biofilms. We report enhanced efficacy for IONPs coated with alginate vs. dextran, and small sizes (~8 nm vs. >20 nm in size) appear to exhibit enhanced antimicrobial efficacy. Human gingival keratinocyte (TIGK) cells in co-culture with treated and untreated multispecies biofilms in an in-vitro periodontitis model also exhibited a trend of reduced inflammatory markers in wells with IONP-treated biofilms. 

Superconducting nanostripe single-photon detectors (SNSPDs) represent key components in silicon quantum photonic integrated circuits (SiQuPICs). They provide good timing precision, low dark counts, and high efficiency. The design, fabrication, and characterization of SiQuPICs comprising SNSPDs coupled to dielectric optical waveguides are the core objectives of our work. The detectors are positioned directly on the dielectric waveguide core to increase photon absorption by the superconducting nanostripes. We also present results on the SPICE circuit modeling of traveling-wave SNSPDs integrated with Si3N4/SiO2 optical waveguides. 

We report on design of traveling-wave superconducting-nanostripe single-photon detectors for integration with silicon quantum photonic integrated circuits, with varying segment lengths and meander numbers. 

We report on design, fabrication, and characterization of silicon quantum photonic integrated circuits comprising superconducting nanostripe single-photon detectors integrated with dielectric optical waveguides. In order to enhance absorption of photons by the superconducting nanostripes, the detectors are located directly on the dielectric waveguide core.