We discuss the design, fabrication, and characterization of silicon-nitride microring resonators for nonlinear-photonic and biosensing device applications. The first part presents new theoretical and experimental results that overcome highly normal dispersion of silicon-nitride microresonators by adding a dispersive coupler. The latter parts review our work on highly efficient second-order nonlinear interaction in a hybrid silicon-nitride slot waveguide with nonlinear polymer cladding and silicon-nitride microring application as a biosensor for human stress indicator neuropeptide Y at the nanomolar level.
- Laser-based mid-IR photothermal spectroscopy (PTS) is a rapid and sensitive analytical method that utilizes advanced laser technology to capture the absorption characteristics of various materials, such as liquids or solids.
- This study utilizes an external cavity quantum cascade laser (EC-QCL) to analyze a thin film of polymethyl methacrylate (PMMA) on a silicon nitride micro-ring resonator, demonstrating its effectiveness in creating an on-chip photothermal sensor.
- The research highlights the optimal alignment and focusing techniques for the laser setup, showing that PTS can lead to compact, efficient sensors suitable for real-time monitoring in industrial applications.
Integrated electro-optic (EO) modulators are the core components of the optoelectronic information technology, and lithium niobate is currently the most widely used crystalline thin film material; however, finite EO coefficients limit the modulation efficiency of the modulators. In this Letter, we present an integrated EO modulator using a microring resonator on the lead zirconate titanate (PZT) and silicon nitride (SiN) heterogeneous platform. The microwave attenuation is reduced by using low loss tangent and dielectric constant SiN as the electrode substrate, achieving an EO bandwidth of 33 GHz.
Polarization-entangled photon pair sources exhibiting nonlocal quantum correlations are crucial to developments of quantum computing, quantum communications, quantum cryptography, and quantum sensing technologies. On-chip polarization entanglement generation thus constitutes one enabling component for integrated quantum photonic circuits. Here, we present to our knowledge the first polarization-entangled photon pair sources in a silicon nitride platform for integrated quantum photonic circuits.
Optical parametric oscillation (OPO) in Kerr microresonators can efficiently transfer near-infrared laser light into the visible spectrum. To date, however, chromatic dispersion has mostly limited output wavelengths to >560 nm, and robust access to the whole green light spectrum has not been demonstrated. In fact, wavelengths between 532 nm and 633 nm, commonly referred to as the "green gap", are especially challenging to produce with conventional laser gain.
We demonstrated, for the first time, micro-ring resonator assisted photothermal spectroscopy measurement of a gas phase sample. The experiment used a telecoms wavelength probe laser that was coupled to a silicon nitride photonic integrated circuit using a fibre array. We excited the photothermal effect in the water vapor above the micro-ring using a 1395 nm diode laser.
