A micro-displacement sensor consisting of a fiber-loop made with a tapered fiber is reported. The sensor operation is based on the interaction between the fundamental cladding mode propagating through the taper waist and higher order cladding modes excited when the taper is deformed to form a loop. As a result, a transmission spectrum with several notches is observed, where the notch wavelength...

A novel tunable whispering gallery modes (WGMs) resonator based on a nematic liquid crystal (LC)-filled capillary and magnetic nanoparticles (MNPs)-coated tapered fiber has been proposed experimentally demonstrated. Thermo-optic tuning of the WGM resonances demonstrated by varying optical pump laser power injected into MNPs-coated half-taper inside capillary. The mechanism relies change effecti...

We demonstrate a direct, single measurement technique for characterizing the dispersion of a photonic crystal waveguide (PCWG) using a tapered fiber evanescent coupling method. A highly curved fiber taper is used to probe the Fabry-Pérot spectrum of a closed PCWG over a broad k-space range, and from this measurement the dispersive properties of the waveguide can be found. Waveguide propagation ...

A fast, high-spatial-resolution detector for high-energy microscopy work is presented. The detector uses a 2160 x 2560 CMOS chip for fast framing (up to 100 Hz in full-frame mode), coupled by a fiber optic taper to a scintillating Terbium-doped fiber optic plate for excellent stopping power even at high energies. The field of view is 7mm × 8.6mm with a resolution of 9 microns. The sensitivity i...

We present an adiabatic taper design in three dimensions for coupling light into photonic crystal defect waveguides in a square lattice of circular dielectric rods. The taper is a two-stage structure in which the first stage makes the transition from a dielectric waveguide to a coupled-cavity waveguide. The second stage subsequently transforms the waveguide mode from an index-guided mode to a b...

The ability to efficiently couple light into and out of semiconductor microcavities is an important aspect of many microphotonic technologies [153], and plays a vital role in chip-based implementations of cavity quantum electrodynamics (cQED) for quantum networking and cryptography [60, 9, 154]. While some geometries, such as micropillar cavities, exhibit highly directional emission that can be...

A moisture sensing technique for real-time monitoring of the content in transformer oil based on an S-taper fiber structure, is proposed and experimentally demonstrated, with advantages high sensitivity, excellent repeatability, simple fabrication, compact structure resistance to ambient temperature variation. By analyzing physical model fiber, quantitative relationship between wavelength chang...

We report an ultra-sensitive and robust fluorescence sensor made by using a biconical taper with a waist diameter of 720 nm for both excitation and fluorescence collection. To enhance the stability of the fluorescence sensor, the biconical taper has been embedded in a 125 µm wide microchannel with a detection length of 2.5 cm. Investigated by measuring the fluorescence intensity of rhodamine 6G...