In this paper we show that by suitably tailoring the dispersion characteristics of a Bragg reflection waveguide (BRW) mode, it is possible to achieve efficient photon pair generation over a large pump bandwidth while maintaining narrow signal bandwidth. The structure proposed consists of a high index core BRW with a periodically poled GaN core and periodically stratified cladding made up of alternate layers of Al(0.02)Ga(0.98)N and Al(0.45)Ga(0.55)N. Such photon-pair generators should find applications in realizing compact and stable sources for quantum information processing.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/oe.16.003577 | DOI Listing |
IUCrJ
January 2025
Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany.
We report the use of streaming data interfaces to perform fully online data processing for serial crystallography experiments, without storing intermediate data on disk. The system produces Bragg reflection intensity measurements suitable for scaling and merging, with a latency of less than 1 s per frame. Our system uses the CrystFEL software in combination with the ASAP::O data framework.
View Article and Find Full Text PDFSensors (Basel)
November 2024
School of Information Engineering, Wuhan University of Technology, Wuhan 430070, China.
Monitoring of real-time flow and defects in the vacuum-assisted resin infusion (VARI) process can provide important guidelines for full impregnation of dry reinforcement. A weak fiber Bragg grating array was employed to obtain quasi-distributed monitoring results in real-time. Sensitivity testing of different kinds of coated optical fiber sensors (OFs) was carried out first, and the polyacrylate-coated OF showed a greater wavelength-shift response than the polyimide-coated one.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Section of Condensed Matter Physics, Department of Physics, National and Kapodistrian University of Athens, University Campus, 15784 Athens, Greece.
The rational design of photonic crystal photocatalysts has attracted significant interest in order to improve their light harvesting and photocatalytic performances. In this work, an advanced approach to enhance slow light propagation and visible light photocatalysis is demonstrated for the first time by integrating a planar defect into CoO-TiO inverse opals. Trilayer photonic crystal films were fabricated through the successive deposition of an inverse opal TiO underlayer, a thin titania interlayer, and a photonic top layer, whose visible light activation was implemented through surface modification with CoO nanoscale complexes.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Clermont Auvergne INP, Université Clermont Auvergne, 63178 Aubière, France.
The use of neutron reflectors is an effective method for improving the quality of neutron sources and neutron delivery systems. In this work, we further develop the method based on the Bragg scattering of neutrons in crystals with large interplanar distances. We compare samples of differently prepared fluorine intercalated graphites by measuring the total cross section for the interaction of neutrons with the samples, depending on the neutron wavelength.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.
After the publication of "Direct formation of hard-magnetic tetrataenite in bulk alloy castings" Ivanov et al., Advanced Science 10 (2022) 2204315, the authors identified a potential misinterpretation of the experimental data. Further work confirms that the original conclusions cannot be supported, and accordingly the paper is retracted.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!