We propose and demonstrate a cost-effective liquid refractive index (RI) sensor in polymer materials by employing Mach-Zehnder interferometer (MZI) formed with the conventional strip waveguide. The proposed can attain high sensitivity choosing suitable reference arm length to reduce optical path difference (OPD) between two arms of employed MZI. Our fabricated devices, which have same sensing 7...

Monolayer molybdenum disulphide (MoS2) has attracted much attention, due to its attractive properties, such as two-dimensional properties, direct bandgap, valley-selective circular dichroism, and valley Hall effect. However, some of its fundamental physical parameters, e.g. refractive index, have not been studied in detail because of measurement difficulties. In this work, we have synthesized h...

We previously established that spectroscopic microscopy can quantify subdiffraction-scale refractive index (RI) fluctuations in a label-free dielectric medium with a smooth surface. However, to study more realistic samples, such as biological cells, the effect of rough surface should be considered. In this Letter, we first report an analytical theory to synthesize microscopic images of a rough ...

We present an analytical method that yields the real and imaginary parts of the refractive index (RI) from low-coherence interferometry measurements, leading to the separation of the scattering and absorption coefficients of turbid samples. The imaginary RI is measured using time-frequency analysis, with the real part obtained by analyzing the nonlinear phase induced by a sample. A derivation r...

Two simple optofluidic devices based on a microprism and a refraction channel, respectively, are proposed for measuring the refractive index of fluids. The microprism chip consists of an optical waveguide channel and a single triangular chamber filled with the test fluid, while the refraction channel chip consists of a single turning channel which functions as a liquid-core/solid-cladding optic...

In this article, we designed and studied silicon oxynitride (SiON) microring-based photonic structures for biosensing applications. We designed waveguides, directional couplers, and racetrack resonators in order to measure refractive index changes smaller than 10-6 refractive index units (RIU). We tested various samples with different SiON refractive indexes as well as the waveguide dimensions ...