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Showing 1 to 20 of 23 for “"q factors"”.
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NIR silicon photodetector enhancement using photonic crystal cavity resonators
… parameter optimization for achieving high Q-factors and extinction ratios specifically for surface-illumination is presented. We report polysilicon PhCC-enhanced sensors with Q-factors of 6500 resulting in responsivities at 1300nm up to 0.13mA/W -a 25x improvement over non-resonant …
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Silica Microspheres Functionalized with Self-assembled Nanomaterials
… to investigate the relationship between cavity Q factors and the amount of nanomaterials deposited onto the silica microspheres. In particular, we fabricate multiple functional microspheres with different ISAM film thickness and Au NPs density. We find that the Q factors of these microspheres are …
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Radiation Pressure induced Nonlinearity in Micro-droplet
… resonators can exhibit very high quality (Q) factors, since the resonator surface can maintain atomic level smoothness. The combination of high Q factors and small resonator volumes has led to a wide range of applications in sensing, optomechanics, nonlinear optics, and quantum optics. In this …
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Detectivity vs. Sensitivity: Non-Hermitian Metasurface Sensor
… large local field enhancements. However, their Q-factors are bad resulting in low detectivity for limited power-budget situations. This problem can be alleviated by using an array of plasmonic structures forming a quasi bound state-in-the-continuum (BIC). The plasmonic BIC sensors show higher …
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Beam-Steerable and Reconfigurable Reflectarray Antennas for High Gain Space Applications
… In addition, an approach to extract the Q factors using full-wave simulations is also presented. Lastly, a detailed study on the effects of inter-element spacing is discussed. Q factor theory discussed in chapter 2 is extended to account for the varying incidence angles and polarizations in …
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Multidoman Piezo-Ceramic Cantilever
… polarization vectors were investigated with Q factors ranging from Q = 50 to Q = 1200, where the acoustical displacements were calculated. Further, the displacements were calculated for a multidomain cantilever model with inversely poled domains and uniform electrode configuration as well as a …
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Microactuators and their application in micro-opto-electro-mechanical systems (MOEMS)
… commonly used in resonators, which need high Q factors. However in some applications, such as optical choppers, they require low Q factors so that they can be operated over a large frequency range. We have designed a comb drive actuator with spring that can be operated from a few Hz up to 5 kHz. …
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Material, acoustic, and mechanical properties of mosquito and midge antennae
… demonstrated strong self-oscillation with high Q-factors. Unlike the mosquitoes, vibrometry of C. riparius showed no relevant self-oscillation of the antenna. Female T. brevipalpis produced self-oscillation but weaker than the male. The three-dimensional pattern of self-oscillation in all …
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Integrating nanostructured artificial receptors with whispering gallery mode optical microresonators via inorganic molecular imprinting techniques
… and contact angle measurements. The quality factors of the devices are measured to evaluate the impact of the coating on device sensitivity. The resulting devices show uniform surface coating with no microstructural damage with Q-factors above 106. This is the first report demonstrating the …
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On-chip single photon sources based on quantum dots in photonic crystal structures
… L3 defect cavities with record Q-factors of up to 5150 were then studied for improved Purcell enhancement of the emission, and in-plane single photon generation from such a device was demonstrated. Finally, an electrically tunable, integrable quantum light source with a total …
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Resonant Detection of Nano to Microscopic Objects Using Whispering Gallery Modes
… linewidth of such a microsphere resonance (Q factors of up to 3x10⁹) allows precise measurement of its frequency. Dielectric microspheres of very high Q are thus the ideal choice for a resonant molecular sensor. Although the resonance is stealth, an evanescent field extends from the …
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A study of stochastic processes in Banach spaces
… Banach space it is shown that, necessarily, Q factors through l2 as a product of 2-summing operators. This factorisation condition is sufficient when the Banach space is of Gaussian type 2. The stochastic integral of a family of operators with respect to a cylindrical Q-Wiener process is shown …
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Integration of glass microspheres and planar waveguides for microsphere lasers
… and Hankel functions. Coupling and quality factors of the waveguide-coupled system are obtained by integrating the overlapped fields of the microsphere and waveguide, and the study of Q factors as a function of sphere/waveguide separation are elaborated. Theoretical models to calculate the …
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Terahertz oscillations of hot electrons in graphene
… separation, and higher harmonics with large Q-factors can also be achieved.
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Radio-Frequency Capacitive Gate-based Sensing for Silicon CMOS Quantum Electronics
… Si NWFET resulting in resonators with loaded Q-factors in the 400-800 range. For a resonator operating at 330 MHz, I have achieved a charge sensitivity of 7.7 $\mu e/\sqrt{\text{Hz}}$ and, when operating at 616 MHz, I get 1.3 $\mu e/\sqrt{\text{Hz}}$. This gate-based sensor can be used for fast, …
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Micro-assembly of integrated photonic devices using a high accuracy transfer printing process
… allows selective mode coupling, with loaded Q-factors reaching ~40,000. The unique advantage of the assembled devices however come from the ability to perform (3) nonlinear processes on SOI without being limited by two-photon absorption and free-carrier losses. Four-wave mixing is shown with …
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The design and realisation of electronically tunable dielectric resonator microstrip filters
… tunable filters. DRs can provide unloaded Q-factors comparable to waveguide resonators (typically 10,000 @ 10GHz), but at a substantially lower weight and smaller volume. DRs are also compatible with a microstrip environment which eliminates the need for microstrip to waveguide adaptors. This …
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Diamond nanophotonic devices for quantum information processing and sensing
… strong Purcell regime with consistently high Q factors while preserving the long spin coherence times of NVs. These systems enable coherent spin control of cavity-coupled semiconductor qubits with coherence times exceeding 200 [mu]s - an increase by two orders of magnitude over previously …
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Experimental study of a high efficiency step-tunable MW gyrotron oscillator
… was designed using the code MAGY and the Q factors of 830 for the TE22,6,1mode at 110 GHz and 1060 for the TE24,7,1 mode at 124.5 GHz would be suitable for CW operation in an industrial gyrotron. The mode converter consisting of a dimpled-wall launcher and 4 phasecorrecting mirrors could …
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Optimization studies of thermal bimorph cantilevers, electrostatic torsion actuators and variable capacitors
… range about 242%. The variable capacitors have Q factors around 100 owing to the use of silicon electrodes other than lower resistivity metal.
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