6 research outputs found
China-EU Energy Cooperation Roadmap 2020 _ Concept Note
The process for the definition of an Energy Cooperation Roadmap between the EU and China was officially initiated at the first meeting of the Energy Security Working Group held in Beijing in February 2013, following the China-EU Joint Declaration on Energy Security of May 2012 that stated the formal establishment of the relationships between China and the EU as energy consumers and strategic partners. This Concept Note on China-EU Energy Cooperation Roadmap 2020 has been elaborated by the Europe-China Clean Energy Centre (EC2) and it provides suggestions on cooperation goals and recommendations for a Roadmap to 202
Massive and parallel 10 Tbit/s physical random bit generation with chaotic microcomb
Abstract Ultrafast physical random bit (PRB) generators and integrated schemes have proven to be valuable in a broad range of scientific and technological applications. In this study, we experimentally demonstrated a PRB scheme with a chaotic microcomb using a chip-scale integrated resonator. A microcomb contained hundreds of chaotic channels, and each comb tooth functioned as an entropy source for the PRB. First, a 12 Gbits/s PRB signal was obtained for each tooth channel with proper post-processing and passed the NIST Special Publication 800-22 statistical tests. The chaotic microcomb covered a wavelength range from 1430 to 1675 nm with a free spectral range (FSR) of 100 GHz. Consequently, the combined random bit sequence could achieve an ultra-high rate of about 4 Tbits/s (12 Gbits/s × 294 = 3.528 Tbits/s), with 294 teeth in the experimental microcomb. Additionally, denser microcombs were experimentally realized using an integrated resonator with 33.6 GHz FSR. A total of 805 chaotic comb teeth were observed and covered the wavelength range from 1430 to 1670 nm. In each tooth channel, 12 Gbits/s random sequences was generated, which passed the NIST test. Consequently, the total rate of the PRB was approximately 10 Tbits/s (12 Gbits/s × 805 = 9.66 Tbits/s). These results could offer potential chip solutions of Pbits/s PRB with the features of low cost and a high degree of parallelism. Graphical Abstrac
Comparison of the laser spot movement inside cylindrical and spherical hohlraums
Compared with cylindrical hohlraums, the octahedral spherical hohlraums have natural superiority in maintaining high radiation symmetry during the whole capsule implosion process in indirect drive inertial confinement fusion. However, the narrow space between laser beams and the hohlraum wall may disturb laser propagation inside the spherical hohlraum. In this work, the laser propagation inside the spherical hohlraum and cylindrical hohlraum is investigated experimentally by measuring laser spot movement at the SGIII-prototype laser facility. The experimental results show that the laser propagations inside the spherical hohlraum and the cylindrical hohlraum are totally different from each other due to different hohlraum structures. For the spherical hohlraum, although the laser energy is mainly deposited in the initial position of the laser spot during the whole laser pulse, some laser energies are absorbed by the ablated plasmas from the hohlraum wall. Because the laser beam is refracted by the thin plasmas near the laser entrance hole (LEH) region, the laser spot in the spherical hohlraum moves toward the opposite LEH. In contrast, the laser spot in the cylindrical hohlraum moves toward the LEH along the laser path due to the plasma expansion. When the laser is to be turned off, the accumulated plasmas near the LEH region in the cylindrical hohlraum absorb a majority of laser energy and hinder the laser arriving at the appointed position on the hohlraum wall. Published by AIP Publishing.National Natural Science Foundation of China [11405011, 11475033, 11305159]SCI(E)ARTICLE72
First Investigation on the Radiation Field of the Spherical Hohlraum
The first spherical hohlraum energetics experiment is accomplished on the SGIII-prototype laser facility. In the experiment, the radiation temperature is measured by using an array of flat-response x-ray detectors (FXRDs) through a laser entrance hole at four different angles. The radiation temperature and M-band fraction inside the hohlraum are determined by the shock wave technique. The experimental observations indicate that the radiation temperatures measured by the FXRDs depend on the observation angles and are related to the view field. According to the experimental results, the conversion efficiency of the vacuum spherical hohlraum is in the range from 60% to 80%. Although this conversion efficiency is less than the conversion efficiency of the near vacuum hohlraum on the National Ignition Facility, it is consistent with that of the cylindrical hohlraums used on the NOVA and the SGIII-prototype at the same energy scale.National Natural Science Foundation of China [11405011, 11475033, 11305159]SCI(E)EIARTICLE211
