Results 131 to 140 of about 74,044 (308)

Ultrahigh‐Order Harmonic Mode‐Locked Optoelectronic Oscillator

Laser &Photonics Reviews, EarlyView.
This article demonstrates a record‐breaking microwave frequency comb generator using an ultrahigh‐harmonic‐order mode‐locked optoelectronic oscillator. By integrating dual recirculating loops into a low‐coherence system, the researchers achieved a harmonic order of 956 with superior noise suppression.
Zhuoran Wang, Santiago Bernal, David V. Plant, Lawrence R. Chen   +3 more
wiley   +1 more source

A new broad K/Ka-band receiver (18.0–32.3 GHz) for the Yebes Observatory’s 40 meter radio telescope★

Astronomy & Astrophysics
Since 2010, the 40 m radio telescope of the Yebes Observatory has been devoted to very long baseline interferometry (VLBI) and single-dish observations. Up until 2019, it covered frequency bands between 2 GHz and 90 GHz in discontinuous and narrow radio ...
López-Pérez J. A., Tercero F., Gallego-Puyol J. D., Albo-Castaño C., Amils-Samalot R., Bautista-Durán M., Barbas L., Beltrán F., Díez-González M., García-Carreño P., García-Merino A., García-Pérez O., Gómez-Molina G., González-García J., López-Fernández I., Malo-Gómez I., Martínez-Parra A., Patino-Esteban M., Tercero B., Marcelino N., Esplugues G., Gallardo Cava I., García-Miró C., Gómez-Garrido M., Santander-García M., Tarrío P., Vidal-García A., de Vicente P., Cernicharo J.   +28 more
doaj   +1 more source

Daris, a low-frequency distributed aperture array for radio astronomy in space [PDF]

, 2010
DARIS (Distributed Aperture Array for Radio Astronomy in Space) is a radio astronomy space mission concept aimed at observing the low-frequency radio sky in the range 1-10 MHz.
Boonstra, A.J., van 't Klooster, K., Falcke, H., Saks, N., Bentum, Marinus Jan   +4 more
core  

Near‐Infrared Polarimetric Imaging With Nonlinear Flat‐Optics

Laser &Photonics Reviews, EarlyView.
ABSTRACT A compact and broadband polarimetric imaging platform is presented, based on second‐harmonic generation (SHG) in nonlinear flat‐optics. The system employs periodic all‐dielectric AlGaAs gratings to induce polarization‐dependent SH emission, enabling pixel by pixel direct retrieval of the full Stokes vector from an input intensity distribution ...
Evgenii Menshikov, Marco A. López Sánchez, Paolo Franceschini, Andrea Tognazzi, Domenico de Ceglia, Kristina Frizyuk, Costantino De Angelis   +6 more
wiley   +1 more source

LOFAR: opening a new window on low frequency radio astronomy

, 2011
Invited talk at the 11th Asian-Pacific Regional IAU Meeting; NARIT Conference Series, Vol. 1; S. Komonjinda, Y. Kovalev, and D. Ruffolo, eds. (8 pages, 6 figures)
Morganti, R., Heald, G., Hessels, J., Wise, M., Alexov, A., De Gasperin, F., Kondratiev, V., McKean, J., Orru`, E., Pizzo, R., van Weeren, R.   +10 more
openaire   +2 more sources

Optical‐to‐Microcomb Stability Transfer for Ultrastable Timing and Microwave/Millimeter‐Wave Generation

Laser &Photonics Reviews, EarlyView.
This work demonstrates a high‐fidelity stability transfer from an optical reference to a high‐repetition‐rate microcomb using a mode‐locked laser bridge. By employing electro‐optic sampling timing detection, femtosecond‐level synchronization and 10−18‐level fractional frequency stability are achieved.
Changmin Ahn, Junyong Choi, Daewon Suk, Hansuek Lee, Jungwon Kim   +4 more
wiley   +1 more source

High time resolution radio astronomy with low-frequency interferometric arrays

, 2014
High time resolution applications of radio astronomy including pulsars and fast radio bursts are proving to be incredibly scientifically rewarding in terms of the depth and breadth of new physics and astrophysics they unveil.
Tremblay, S., Van Straten, W., Deshpande, A., Ord, Stephen, Tingay, Steven, Bhat, N.   +5 more
core   +1 more source

Revealing the Resonant Physics of Open Photonic Time Crystals

Laser &Photonics Reviews, EarlyView.
ABSTRACT Photonic time crystals (PTCs) are media whose permittivity is modulated periodically in time, enabling momentum bandgaps and parametric amplification of light. Their realization at the nanoscale can revolutionize the study of light‐matter interactions.
Adrià Canós Valero, Sergei Gladyshev, David Globosits, Stefan Rotter, Egor A. Muljarov, Thomas Weiss   +5 more
wiley   +1 more source

Epitaxial Integration of III–V Membrane Photodetectors With Lateral p–i–n Junctions on the Silicon‐On‐Insulator Waveguide Platform

Laser &Photonics Reviews, EarlyView.
Epitaxial growth forms III–V membranes directly atop the silicon waveguide layer on SOI, while in‐plane in situ doping defines lateral p–i–n InP/InGaAs junctions in a single growth step. The membrane photodetectors achieve 50 Gb/s NRZ‐OOK operation.
Zhao Yan, Yifu Chen, Martin Ebert, Ka Ming Wong, Wenjie Wang, Tim Grieb, Florian F. Krause, Andreas Rosenauer, Graham T. Reed, David J. Thomson, Qiang Li   +10 more
wiley   +1 more source

An investigation of a frequency diverse array

, 2009
This thesis presents a novel concept for focusing an antenna beam pattern as a function of range, time, and angle. In conventional phased arrays, beam steering is achieved by applying a linear phase progression across the aperture.
Antonik, P.
core