Open Conference Systems
Not a member yet
683 research outputs found
Sort by
Optical Fiber Sensors and Their Applications
No full textSeveral novel fiber-based sensors and technologies developed are presented here, including fiber Bragg grating (FBG) based sensors, photonic crystal fiber (PCF) based sensors, specialty fiber-based sensors and distributed fiber sensing systems
A Multilayer Notch Band Printed Duplex Dipole Antenna for Ku-band Applications
No full textA band reject broadband antenna with bandwidthof 8.82 GHz operating in the Ku-band realized in multilayerconfiguration is proposed in this paper. The band rejection hasbeen achieved by introducing Split Ring Resonators (SRRs).The multilayer topology adopted in this paper has resulted inan overall antenna size of 22 x 12 x 2:285 mm^3. Such topology allows an additional benefit of loading the middle layer with SRRs to reject a specific frequency
Multiphysics simulations for phase change material based nanophotonics
No full textThe growing demand on reconfigurability in neuromorphic computing, quantum computing and microwave photonics is attracting increasing attention towards design and optimization of active integrated photonic components. Phase change materials are materials in which phase transitions can be induced quickly and reversibly, resulting in pronounced changes of their physical properties. In this presentation we report on recent developments and applications of a multiphysics description of phase change material based nanophotonic systems
Generalized Snell-Descartes laws for metasurfaces made by scatterers
No full textThis talk will discuss the relevance of the generalized laws of reflection and refraction for metasurfaces. We discuss in detail their derivation starting from questioning the original proof. We discuss diffractive metasurfaces made of scatter- ers. We conclude that generalized Snell-Descartes laws can be defined but differ from the ones reported in the literature
Plasmonic and metamaterial devices based on highly doped semiconductors for infrared applications
No full textHighly doped semiconductors are ideal materials to realize plasmonic and metamaterial based systems operating from the infrared to the THz frequencies. In this work, we show that nano-antennas, hyperbolic metamaterials and epsilon-near-zero metasurfaces can be designed which such materials. These systems are demonstrated to enhance light matter interactions and can be applied for infrared spectroscopy
New results on the range of responses that two-phase composites can have to time varying fields
No full text40 years ago bounds were found on the effective complex dielectric constant of two-phase composites. We show that one bound can be tightened and then is optimal. New geometries with moduli on the remaining arc are found. We also bound the quasistatic response to fields with any variation in time. Curiously, measurements at specific times can directly yield the volume fractions of the phases. We show how applied fields can be tailored to have this property
Breaking the limit of emission suppression in low contrast 3D media
No full textLight emission can be significantly suppressed in 3D photonic crystals at the frequency of a photonic band gap but a refractive index contrast above 1.8 is needed. We present 3D quasiperiodic structures that can significantly reduce the density of states even at lower index contrasts. The suppression of 10 dB is demonstrated in simulations with refractive index contrast of 1.4. A refractive index contrast of 1.6 is investigated experimentally in microwave regime
Critical distances for near-ground propagation: application to dipole antennas
No full textThis paper deals with the problem of near ground wave propagation, and in particular with the assessment of the region in which the near-ground wave becomes the dominant component. The critical distances are estimated as a function of the link parameters in the case of dipole antennas
Fast Surrogate Models of Dual-Reflector Antennas Noise Temperature for Radio Astronomy
No full textDual-reflector antennas are a popular choice for high performance modern interferometric radio telescope systems. They provide several advantages over single reflector antennas. Efficient design of these systems for optimal sensitivity performance is challenging – largely due to the computational effort involved in calculating the antenna temperature of the system in a numerical optimization loop. A fast and accurate surrogate model for the antenna temperature, that can be used in an optimization loop, is presented
Spectral tuning of SPP reflection by quasi-symmetric metal nano-block arrays
No full textWe investigate the spectral tuning of the SPP wave packets by quasi-symmetric arrays composed of metal blocks with two different structural lengths. The FDTD simulations showed a resonance phenomenon in the gap between the blocks when the two blocks have different lengths in the longitudinal direction. Furthermore, the resonance of the gap resulted in a significant spectral modulation of the reflected SPP wave that depended on the structural length and positional relationship of the blocks