Related papers: Enhanced sensitivity of an all-dielectric refracti…
We consider refractive index sensing with optical bounds states in the continuum (BICs) in dielectric gratings. Applying a perturbative approach we derived the differential sensitivity and the figure of merit of a sensor operating in the…
A highly sensitive refractive index sensor based on grating-assisted strip waveguide directional coupler is proposed. The sensor is designed using two coupled asymmetric strip waveguides with a top-loaded grating structure in one of the…
Dynamic optical sensors, as those based on the reflectivity of isotropic dielectrical interfaces, can be useful for measuring small changes in the refractive index of fluid media. Exact and approximated explicit formulas for their…
Although all-dielectric sensors exhibit minimal absorption and a high figure of merit (FOM), their sensitivity is significantly lower compared to plasmonic sensors. One approach to enhancing the sensitivity of dielectric sensors is…
The optimization of integrated optical evanescent-wave sensors is dual. For optimal performances, we require waveguides with both maximal sensitivity to the measurand, the quantity intended to be measured, and minimal sensitivities to…
Addressing the temperature and strain induced cross-talks simultaneously, we propose an inherently strain and temperature insensitive fiber-optic bio-sensor. The insensitivity has been achieved by properly adjusting the dopants and their…
A refractive index sensor based on a semicircular bent fiber is presented. The interference occurs between the cladding mode excited in the bending region and the core mode. Both the theoretical and experimental results show that the…
Sensing schemes based on Rayleigh anomalies (RAs) in metal nanogratings exhibit an impressive bulk refractive-index sensitivity determined solely by the grating period. However, the surface sensitivity (which is a key figure of merit for…
Biological sensory systems generally operate out of equilibrium, which often leads to their improved performance. Here, we study the sensitivity of ligand concentration for a general receptor model, which is generally in the non-equilibrium…
We have implemented a multi-functional optofluidic sensor that can monitor changes in the refractive index and pressure of biofluid simultaneously and can detect free-solution molecular interaction in-situ. In this paper, we demonstrate two…
Wavy dielectric grating hosts bound states in the continuum (BICs) at nonzero Bloch wave number. For oblique incident optical field with parameters near to the BICs, the reflectance spectrum exhibits ultra-sharp Fano line shape, and the…
The use of relatively simple structures to achieve high performance refractive index sensors has always been urgently needed. In this work, we propose a lithography-free sensing platform based on metal-dielectric cavity, the sensitivity of…
We present highly sensitive refractometers based on a long-period grating in a large mode area PCF. The maximum sensitivity is 1500 nm/RIU at a refractive index of 1.33, the highest reported for any fiber grating. The minimal detectable…
Compensating the temperature induced phase-changes of concatenated dual-resonance long-period-gratings by a suitably chosen inter-grating material and space we report wide-range temperature insensitivity along with extremely high…
We configure and analyze a nanostructured device that hybridizes grating modes and surface plasmon resonances. The model uses an effective index of refraction that considers the volume fraction of the involved materials, and the propagation…
A modified weak measurement scheme, rotatory biased weak measurement, is proposed to significantly improve the sensitivity and resolution of the refractive index sensor on a total reflection structure. This method introduces an additional…
We study theoretically the responsivity of optical modulators. For the case of linear response we find using perturbation theory an upper bound imposed upon the responsivity. For the case of two mode modulator we find a lower bound imposed…
In this work the behavior of optical micro-ring resonators, especially when functioning as refractive index sensors, is studied in detail. Two configurations are considered, namely a linear waveguide coupled to a circular one and two linear…
We describe a design methodology for modifying the refractive index profile of graded-index optical instruments that incorporate singularities or zeros in their refractive index. The process maintains the device performance whilst resulting…
We report a refractive index sensor comprising of unique T grating on top of periodic nano-cavities. The sensor has two resonant modes sensitive to different regions of the structure with low inter-region interference, hence allows…