Multiplexing temperature-compensated open-cavity Fabry-Perot sensors at a fiber tip.

We investigate multiplexing of four highly sensitive Fabry-Perot (FP) microresonators at the tip of a single-mode optical fiber for refractive index (RI) measurements with simultaneous temperature compensation. The individual sensing elements for RI or temperature consist of either open-cavity FP resonators or solid fiber core regions fabricated by diamond-blade dicing of single-mode optical fibers, respectively. The reflectivity of the open resonators is further enhanced by matched dielectric coatings.

Watt-level 775 nm SHG with 70% conversion efficiency and 97% pump depletion in annealed/reverse proton exchanged diced PPLN ridge waveguides.

We report on fabrication of ridge waveguides formed in congruent periodically poled lithium niobate substrates using annealed and reverse proton exchange followed by diamond blade dicing. 1 W of second-harmonic generation at 775 nm has been obtained in a single-pass in 50 mm long ridge waveguides with internal conversion efficiency of 70%. At this power level, 97% pump depletion has been reached.

Fiber-optic sensor measuring spatial distributions of refractive index and temperature.

In this work, we present a fiber sensor designed to measure simultaneously spatial inhomogeneities of the refractive index and temperature in liquid media, for example, induced by biochemical reactions. The sensor's constituent elements are Fabry-Perot microresonators fabricated in standard single-mode optical fibers by diamond blade dicing. To allow simultaneous measurements of different refractive indices, the sensor comprises two open cavities approximately 2 mm apart.

Efficient Nd:Ti:LiNbO ridge waveguide lasers emitting around 1085 nm.

In this work, we report on efficient neodymium-doped titanium in-diffused ridge waveguide lasers in x-cut congruent LiNbO under excitation at 814 nm. For the sample fabrication we used our novel technique of three-side evaporation and in-diffusion for Nd and Ti incorporation into pre-defined ridges. Due to improved photorefractive damage resistance by indium tin oxide (ITO) coating we achieved stable laser operation at 1084.

Dual parameter fiber-integrated sensor for refractive index and temperature measurement based on Fabry-Perot micro-resonators.

We report on a miniature all-fiber dual parameter sensor capable of simultaneous measurement of the refractive index (RI) and temperature of fluids and gases. The high-sensitivity sensing element is comprised of two Fabry-Perot (FP) micro-resonators fabricated in a single-mode fiber and has a total length of <100  μm. The RI sensing cavity is formed by diamond blade dicing, whereas a thinner silicon inlay glued into it serves as a temperature sensor.