Browsing Institutt for elektroniske systemer by Journals "Optics Express"
Now showing items 1-13 of 13
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Acoustooptic characterization of a birefringent two-mode photonic crystal fiber
(Journal article; Peer reviewed, 2006)The effect of axial variations in acoustooptic phase-mismatch coefficient of a two-mode birefringent photonic crystal fiber (PCF) is studied experimentally using two different methods. The first method is to determine axial ... -
Controlling an actively-quenched single photon detector with bright light
(Journal article; Peer reviewed, 2011)We control using bright light an actively-quenched avalanche single-photon detector. Actively-quenched detectors are commonly used for quantum key distribution (QKD) in the visible and near-infrared range. This study shows ... -
Detection of single nano-defects in photonic crystals between crossed polarizers
(Peer reviewed; Journal article, 2013)We investigate, by simulations and experiments, the light scattering of small particles trapped in photonic crystal membranes supporting guided resonance modes. Our results show that, due to amplified Rayleigh small particle ... -
Finite-size limitations on quality factor of guided resonance modes in 2D photonic crystals
(Journal article; Peer reviewed, 2013)High-Q guided resonance modes in two-dimensional photonic crystals, enable high field intensity in small volumes that can be exploited to realize high performance sensors. We show through simulations and experiments how ... -
Heterodyne interferometer for absolute amplitude vibration measurements with femtometer sensitivity
(Journal article; Peer reviewed, 2013)A heterodyne interferometer for highly sensitive vibration measurements in the range 100kHz − 1.3GHz is presented. The interferometer measures absolute amplitude and phase. The signal processing of the setup is analyzed ... -
High-performance stationary solar tracking through multi-objective optimization of beam-steering lens arrays
(Peer reviewed; Journal article, 2020)Beam-steering lens arrays enable solar tracking using millimeter-scale relative translation between a set of lens arrays. This may represent a promising alternative to the mechanical bulk of conventional solar trackers, ... -
Multilevel Maxwell-Bloch simulations in inhomogeneously broadened media
(Journal article; Peer reviewed, 2011)A compact numerical method for simulating ultrafast pulse interaction with inhomogeneously broadened multi-level media is reported. We use a low-dispersion pseudospectral scheme with fourth order time stepping for Maxwell’s ... -
Optical parametric master oscillator and power amplifier for efficient conversion of high-energy pulses with high beam quality
(Journal article; Peer reviewed, 2004)We describe a system for parametric conversion of high-energy, Q-switched laser pulses from 1.064 µm to 2.1 µm in KTiOPO4. High beam quality and efficiency are obtained by use of a two-stage system: An optical parametric ... -
Photonic-crystal membranes for optical detection of single nano-particles, designed for biosensor application
(Peer reviewed; Journal article, 2012)A sensor designed to detect bio-molecules is presented. The sensor exploits a planar 2D photonic crystal (PC) membrane with sub-micron thickness and through holes, to induce high optical fields that allow detection of ... -
Simulations and realizations of active right-handed metamaterials with negative refractive index
(Journal article; Peer reviewed, 2007)The theory of determining the sign of the refractive index in active materials is discussed. Animations of numerical simulations are presented, supporting the claim that negative refractive index may occur in right-handed ... -
Total internal reflection and evanescent gain
(Journal article; Peer reviewed, 2011)Total internal reflection occurs for large angles of incidence, when light is incident from a high-refractive-index medium onto a low-index medium. We consider the situation where the low-index medium is active. By invoking ... -
Waveguide asymmetric long-period grating couplers as refractive index sensors
(Peer reviewed; Journal article, 2020)A highly sensitive integrated photonic transducer is designed by utilizing asymmetric long-period gratings on a silicon waveguide. These gratings are formed by periodic perturbation of the waveguide width, leading to ... -
Wide frequency range measurements of absolute phase and amplitude of vibrations in micro- and nanostructures by optical interferometry
(Journal article; Peer reviewed, 2007)A heterodyne interferometer has been built in order to characterize vibrations on micro- and nanostructures. The interferometer offers the possibility of both absolute phase and high resolution absolute amplitude vibrational ...