Quantum emitters are essential for quantum optics and photonic quantum information technologies. To date, diverse quantum emitters such as single molecules, quantum dots, and color centers in diamond have been integrated onto chips by various methods which typically have complex operation. Here, our quantum emitters are colloidal CdSe/ZnS quantum dots (QDs) embedded in polymeric nanostructures. We report two approaches based on photo-polymerization for deterministically integrating quantum emitters on chips. Firstly, based on one-photon polymerization (OPP), we coupled an external excitation laser into surface ion exchanged waveguides (IEWs), the surface evanescent wave resulting in the QD-polymer ridges. In order to scale down the dimension of the QD-polymer structures, we secondly fabricated QD-polymer nano-dots on glass substrates by a direct laser writing platform (DLW) based on two-photon polymerization (TPP). A deep fabricating parameters study has been made enable us to control the dimensions of the polymer-QDs nanocomposites. Moreover, photoluminescence (PL) measurement results demonstrate the feasible and potential of our method for integrating quantum emitters onto future complex photonic chips.
The cointegration of optical and microfluidic functions on chemically resilient borosilicate glass to provide microfluidic chemical analyses is described. An evanescent wave sensing chip containing a fluid channel of 21 μL is implemented to carry out absorption spectroscopy measurements in the near-infrared range. Microchip packaging allows to perform remote analysis of harsh chemical solutions in confined environments. Detection of plutonium(VI) in aqueous 1 mol/L nitric acid solutions is achieved on solutions ranging from 0.05 to 0.13 mol/L. Results showcase the validity of the proposed approach by obtaining a sensor calibration curve and chip resilience to highly concentrated strong acids and radioactive elements. This proof-of-concept opens the path to optimized devices with a lower limit of detection.
Research in nuclear safety and fuel reprocessing has led to a surging need for novel chemical analysis tools with reduced analyte and effluent volumes. Recent technological advances for the elaboration and packaging of glass optofluidic co - integrated sensors have opened up the way for said analysis in harsh environments. We discuss a sensor engineering approach for the construction of an integrated absorption spectrometer with an ion-exchange core. Pu(VI) oxidation state exhibits a major absorption peak at a wavelength of 831 nm with a molar absorption coefficient of 545 L.mol-1.cm-1. An evanescent waveguiding sensing structure that allows guided fluid/light interaction is investigated in order to provide absorption spectroscopy measurements. The work presented consists of optical simulations as well as experimental measurements. Waveguide engineering with respects to modal transmission, field/fluid interaction coefficient Γ and device losses is presented. The simulations are carried out by computing ion-exchanged waveguide refractive index distribution and using it in mode solver software. Device optical characterization and bench tests are carried out to verify approach viability. First device measurements of a neodymium absorption peak in nuclear manipulation conditions are displayed.
Advances in nuclear fuel reprocessing have led to a surging need for novel chemical analysis tools. In this paper, we present a packaged lab-on-chip approach with co-integration of optical and micro-fluidic functions on a glass substrate as a solution. A chip was built and packaged to obtain light/fluid interaction in order for the entire device to make spectral measurements using the photo spectroscopy absorption principle. The interaction between the analyte solution and light takes place at the boundary between a waveguide and a fluid micro-channel thanks to the evanescent part of the waveguide’s guided mode that propagates into the fluid. The waveguide was obtained via ion exchange on a glass wafer. The input and the output of the waveguides were pigtailed with standard single mode optical fibers. The micro-scale fluid channel was elaborated with a lithography procedure and hydrofluoric acid wet etching resulting in a 150±8 μm deep channel. The channel was designed with fluidic accesses, in order for the chip to be compatible with commercial fluidic interfaces/chip mounts. This allows for analyte fluid in external capillaries to be pumped into the device through micro-pipes, hence resulting in a fully packaged chip. In order to produce this co-integrated structure, two substrates were bonded. A study of direct glass wafer-to-wafer molecular bonding was carried-out to improve detector sturdiness and durability and put forward a bonding protocol with a bonding surface energy of γ>2.0 J.m-2. Detector viability was shown by obtaining optical mode measurements and detecting traces of 1.2 M neodymium (Nd) solute in 12±1 μL of 0.01 M and pH 2 nitric acid (HNO3) solvent by obtaining an absorption peak specific to neodymium at 795 nm.
The development of pulsed lasers allows increasing the power density into integrated waveguides to a level compatible with the generation of nonlinear phenomena, opening the route to the realization of integrated supercontinuum sources. In this paper, we investigate the spectral broadening of a laser pulse through Raman scattering processes in normal dispersion regime with nanosecond pumping. The obtained experimental results are compared to an experimental model based on a single fiber with the same confinement and perspectives in terms of integrated broadband sources are presented.