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Showing 1 to 14 of 14 for “"grating coupler"”.
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Optimized grating coupler designs for integrated photonics
… research deals with the optimization of complex grating couplers for SOI platforms to couple light from a specific coupling scheme and it is divided in 4 sections. First, Chapter 2 presents in details the customized design routine, developed during my PhD, based on a Particle Swarm Optimization, …
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Theory, Design, and Fabrication of Diffractive Grating Coupler for Slab Waveguide
… theory design and fabrication of a diffractive grating coupler. The first part of the design process is to choose the period of the grating coupler based on the desired coupling angle. The second part of the design process is to choose the geometry of the grating that gives maximum coupling …
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Multi-channel solutions for optical labelfree detection schemes based on the interferometric and grating coupler principle
… units are of importance for HTS. Here embossed gratings which may act as transducers or coupling elements in the sensor units are characterized and investigated. The gratings have been embossed in glass, Sol-Gel or Ormocer. Different concepts where embossed gratings may be implemented for HTS …
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Hybrid mode coupling for enhanced sensing and integrated photonics
… components had to be CMOS compatible. The grating coupler, a key integration component, is coupled to a vertical-cavity microlaser to power the optical circuit. For practical realization, the coupling is at normal incidence, and the grating coupler is buried within oxide to ease flip-chip …
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Optical properties of III-V semiconductors
… mode at a time using a real-space diffraction grating coupler. The resulting eigenmode distributions were used to obtain the refractive index of GaAs at a matrix of sub bandgap photon energies (1.40 eV $<$ h$\nu <$ 1.50 eV) and temperatures (40 K $<$ T $<$ 300 K). Values for the temperature …
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Monolithic Integration Of Dual Optical Elements On High Power Semicond
… the AlGaAs/GaAs waveguide by a low reflectivity grating coupler towards the substrate where a second monolithic optical element is integrated to improve the device performance or functionality. A fabrication process based on electron beam lithography and plasma etching was developed to control …
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Integrated Wavelength Stabilization Of Broad Area Semiconductor Lasers Using A Dual Grating Reflector
… wavelength stabilization scheme based on grating-coupled surface-emitting lasers is explored. This wavelength stabilization scheme relies on two gratings. The first grating is fabricated on the p-side of the semiconductor laser in close proximity to the laser waveguide such that it couples …
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Fabrication and applications of fibre Bragg gratings
The consequences of fabricating Bragg gratings in various fibres, with or without hydrogen loading, and with varying laser power levels are explored. Three new techniques for fabricating chirped gratings are presented. Beams with dissimilar wavefront curvatures are interfered to give chirped …
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Integrated silicon photonic two-dimensional grating couplers
… for a simple interfacing is the diffraction grating coupler (GC). In its most basic, one-dimensional implementation, a silicon waveguide mode is laterally enlarged by a taper structure, feeding a periodically etched grating. The latter deflects the light under a small angle with respect to …
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Tunable and High Refractive Index Polydimethylsiloxane Polymers for Label-Free Optical Sensing
… A simple planar waveguide sensor with an input grating coupler was developed to monitor changes in refractive index of the cladding through shifts in peak resonance wavelength. Using high refractive index PDMS materials as the waveguide core, we monitored changes in refractive index arising from …
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Stimulated Brillouin scattering in an on-chip microdisk resonator
… resonator coupled by means of waveguide and gratings to realize on-chip SBS. Our COMSOL simulations show that the phase matching condition is possible between the first- and second-order transverse optical modes in the wavelength range of interest (1.52 μm-1.57 μm) by adjusting the dimension …
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Design, fabrication, and characterization of lithium niobate whispering-gallery-mode microdisk and microring resonators and grating couplers
… microdisk resonators, a single-ring filter, and grating couplers. The theory, simulation, fabrication, and experimental results of these devices are presented. Fabricated grating couplers with center wavelengths around 1560 nm are characterized and their insertion losses are explained. Microring …
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Development of microcantilever mid-infrared detectors and sources and their application in infrared spectroscopy
… the integration of one-dimensional high-contrast grating into silicon-aluminum bimaterial cantilevers which enhances the amplitude and bandwidth of the IR absorbance as well as the responsivity. With the integrated grating, the silicon layer acts as a grating coupler and waveguide, while the …
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Aktivitätsmessung auf nukleinsäuremodifizierten Oberflächen
Im Bereich der medizinischen Diagnostik spielen DNA-Chips eine immer wichtigere Rolle. Dabei werden Glas- oder Silikon-Oberflächen mit Tausenden von einzelsträngigen DNA-Fragmenten, sog. Sonden, bestückt, die mit den passenden DNA-Fragmenten in der zugefügten Patientenprobe verschmelzen. Die …