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Dmitry Pidgayko

Publications and source records attributed to Dmitry Pidgayko.

2 recordsLinked to original sources

Sensitive biodetection in flow using metasurface hosting quasi-bound state in the continuum resonances

We have designed optical metasurfaces hosting high-quality factor quasi-bound state in the continuum (q-BIC) resonances for optical biosensing in flow. The unit cell of the metasurface contains two rectangular bars. An asymmetry factor is introduced by varying the gap width between the bars, to enable optical coupling to a q-BIC resonance confined to the air gap between neighboring nanoresonators. The location of the resonances makes them highly sensitive to changes in the local refractive index, leading to experimental bulk refractive index sensitivities exceeding 315 +/- 22 nm/RIU and a figure-of-merit of 66 +/- 5 RIU-1. Successful streptavidin-biotin binding was observed by measuring the metasurface transmission in real-time by exposing the metasurface to various concentrations of analytes via a commercial microfluidic flow cell apparatus. The experimental limit of detection, defined as 3σ above noise, was found to be 1.8x10-8 M. This platform represents a compact optical approach for point-of-care diagnostics with fast read-out.

physics.optics

Voltage-tunable OPO with an alternating dispersion dimer integrated on chip

Optical parametric oscillators enable the conversion of pump light to new frequency bands using nonlinear optical processes. Recent advances in integrated nonlinear photonics have led to create compact, chip-scale sources via Kerr nonlinearity-induced parametric oscillations. While these sources have provided broadband wavelength tuning, the ability to tune the emission wavelength via dynamically altering the dispersion, has not been attained so far. Here we present a voltage-tunable, on-chip integrated optical parametric oscillator based on alternating dispersiondimer, allowing to tune the emission over nearly 20 THz near 1550 nm. Unlike previous approaches, our device eliminates the need for a widely tunable pump laser source and provides efficient pump filtering at the drop port of the auxiliary ring. Integration of this scheme on a chip opens up the possibility of compact and low-cost voltage-tunable parametric oscillators with diverse application possibilities.

physics.optics