Waveguide with grating couplers

Figure 1. Tapered slab-type MNA single crystal film waveguide with grating couplers.

Conceptual structure of four-layered waveguide with grating coupler for all optical bistability. 

Sugihara, O., Toda, T., Ogura, T., Kinoshita, T., and Sasaki, K., Phase-matched second-harmonic generation in a four-layer 2-methyi-4-nitroaniIine waveguide with grating couplers. Opt. Lett., 16, 702-704 (1991). 

Thin Film MNA Crystal Waveguides for Phase-matched SHG with Grating Couplers... 

A) Sealed type thin film MNA crystal waveguide for phase matched SHG was realized with grating couplers. This type of structure is advantageous because of separation from ambient atmosphere. 

All Optical Bistability of Vacuum Evaporated Polydiacetylene (PDA.12-8) Film Waveguide with a Grating Coupler... 

For refractive-index-type sensors, the waveguide is intrinsically the sensing element, and then chemical processes are measured with the variations of the refractive index, n, of guided modes. The majority of the various sensor types and published configurations make use of grating couplers (Fig. 10a) [83,84], resonant mirrors (Fig. 10b) [52,86-89] or interferometric sensors (Fig. 11) as... 

The use of a grating to facilitate the out-coupling has been demonstrated [52]. In that work, a (methyl-3 -(p-nitro-phenyl)carbazate, MNCZ) crystal was used as the substrate with a slab transparent waveguide made of photoresist deposited on top. The grating coupler was fabricated holographically and the SHG of a Nd YAG 1.06 pm laser demonstrated. This nonlinear crystal has a nonlinear d36 coefficient of 22.7 pm V-1 (3 time larger than d24 of KTP) and a cut-off wavelength of 455 nm. Reported conversion efficiencies were at that time limited by lack of sufficient crystal flatness. 

An electro-active integrated optical waveguide (EA-lOW) with a separation of 8 mm between the input and output grating couplers was used to experimentally assess the sensitivity of EA-lOW-based measurements on surface-confined films. Measurements performed on adsorbed MB (e = 7,800 M cm at 633 nm) at a... 

In the optical system of an SPR sensor, surface plasmons are optically excited and the SPR signal is encoded into a light wave interacting with the surface plasmons. Based on the method of excitation of surface plasmons, SPR sensors can be classified as SPR sensors based on (i) prism couplers, (ii) grating couplers, and (iii) waveguide couplers (Fig. 4). 

Wei X, Kang C, Rong G, Retterer ST, Weiss SM (2009) Porous silicon waveguide with integrated grating coupler for DNA sensing. In Fauchet PM (ed) Frontiers in pathogen detection from nanosensors to systems, vol. 7167, SPIE... 

SAM adsorption was also followed in situ by optical waveguide hghtmode spectroscopy (OWLS) by means of a grating coupler system (GKR 401, Fraunhofer-Institut fiir Physikalische Mess-technik, Freiburg, Germany). Prior to starting adsorption experiments, the basehne was stabilized with the pure solvent. For kinetic measurements, a solution of ODP was pumped at 1 mli/s through the fluid cell at room temperature and the adsorption of ODP was followed in real time. 

Oxides of transition metals, such as niobium, tantalum, or titanium, are suitable as waveguiding layers on optical (grating coupler) waveguides due to their high refractive index and transparency. Therefore, oxide-coated chips are used as sensing devices in technology based on the interaction of a laser-induced evanescent field with analyte constituents adsorbed on or immobilized at the waveguide/ fluid interface. ... 

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