biostudies-literatureLarson KNational Institutes of HealthNIGMS NIH HHS4650-4653https://www.ebi.ac.uk/biostudies/studies/S-EPMC9362736biostudies-literatureUnknown46(18)We demonstrate a method of tuning the resonant frequencies of silicon microring resonators using a 3D-printed microfluidic chip overlaid directly on the photonic circuit with zero energy consumption following the initial tuning. Aqueous solutions with different concentrations of NaCl are used in experimentation. A shift of a full free spectral range is observed at a concentration of 10% NaCl. On a 60 µm microring resonator, this equals a resonant wavelength shift of 1.514 nm when the index of the cladding changes by 0.017 refractive index units (RIUs), or at a rate of 89.05 nm/RIU.Optics lettersPost-fabrication tuning of microring resonators using 3D-printed microfluidics.PMC93627362R15GM12305-02R15 GM123405Carver CHammond ANordin GLarson KViglione MBoaks MAnderson DCamacho RMfalsePost-fabrication tuning of microring resonators using 3D-printed microfluidics.We demonstrate a method of tuning the resonant frequencies of silicon microring resonators using a 3D-printed microfluidic chip overlaid directly on the photonic circuit with zero energy consumption following the initial tuning. Aqueous solutions with different concentrations of NaCl are used in experimentation. A shift of a full free spectral range is observed at a concentration of 10% NaCl. On a 60 µm microring resonator, this equals a resonant wavelength shift of 1.514 nm when the index of the cladding changes by 0.017 refractive index units (RIUs), or at a rate of 89.05 nm/RIU.2021-01-01T00:00:00Z2021 Sep2025-04-19T05:57:38.793Z2025-04-19T05:57:38.793ZS-EPMC93627363452507310.1364/ol.43398710.1364/OL.433987