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981.
WeiPing Liu ZhiHong Li JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 相似文献
982.
LiXia Zhao ShiChao Zhu ChunHui Wu Chao Yang ZhiGuo Yu Hua Yang Lei Liu 《中国科学:物理学 力学 天文学(英文版)》2016,59(10):107301
Rapid improvement in the efficiency of GaN-based LEDs not only speed up its applications for general illumination, but offer the possibilities for data transmission. This review is to provide an overview of current progresses of GaN-based LEDs for light communications. The modulation bandwidth of GaN-based LEDs has been first improved by optimizing the LED epilayer structures and the modulation bandwidth of 73 MHz was achieved at the driving current density of 40 A/cm2 by changing the multi-quantum well structures. After that, in order to increase the current density tolerance, different parallel flip-chip micro-LED arrays were fabricated. With a high injected current density of ~7900 A/cm2, a maximum modulation bandwidth of ~227 MHz was obtained with optical power greater than 30 mW. Besides the increase of carrier concentrations, the radiative recombination coefficient B was also enhanced by modifying the photon surrounding environment based on some novel nanostructures such as resonant cavity, surface plasmon, and photonic crystals. The optical 3 dB modulation bandwidth of GaN-based nanostructure LEDs with Ag nanoparticles was enhanced by 2 times compared with GaN-based nanostructure LEDs without Ag nanoparticles. Our results demonstrate that using the QW-SP coupling can effectively help to enhance the carrier spontaneous emission rate and also increase the modulation bandwidth for LEDs, especially for LEDs with high intrinsic IQE. In addition, we discuss the progress of the faster color conversion stimulated by GaN-based LEDs. 相似文献
983.
Variable electron-phonon coupling in isolated metallic carbon nanotubes observed by Raman scattering
Wu Y Maultzsch J Knoesel E Chandra B Huang M Sfeir MY Brus LE Hone J Heinz TF 《Physical review letters》2007,99(2):027402
We report the existence of broad and weakly asymmetric features in the high-energy (G) Raman modes of freely suspended metallic carbon nanotubes of defined chiral index. A significant variation in peak width (from 12 cm(-1) to 110 cm(-1)) is observed as a function of the nanotube's chiral structure. When the nanotubes are electrostatically gated, the peak widths decrease. The broadness of the Raman features is understood as the consequence of coupling of the phonon to electron-hole pairs, the strength of which varies with the nanotube chiral index and the position of the Fermi energy. 相似文献
984.
Zhao JF Ou HW Wu G Xie BP Zhang Y Shen DW Wei J Yang LX Dong JK Arita M Namatame H Taniguchi M Chen XH Feng DL 《Physical review letters》2007,99(14):146401
The electronic structure of a new charge-density-wave system or superconductor, 1T-Cu(x)TiSe(2), has been studied by photoemission spectroscopy. A correlated semiconductor band structure is revealed for the undoped case, which resolves a long-standing controversy in the system. With Cu doping, the charge-density wave is suppressed by the raising of the chemical potential, while the superconductivity is enhanced by the enhancement of the density of states, and possibly suppressed at higher doping by the strong scattering. 相似文献
985.
Wu Y Toccoli T Koch N Iacob E Pallaoro A Rudolf P Iannotta S 《Physical review letters》2007,98(7):076601
The key role of the pentacene kinetic energy (Ek) in the early stages of growth on SiOx/Si is demonstrated: islands with smooth borders and increased coalescence differ remarkably from fractal-like thermal growth. Increasing Ek to 6.4 eV, the morphology evolves towards higher density of smaller islands. At higher coverage, coalescence grows with Ek up to a much more uniform, less defected monolayer. The growth, interpreted by the diffusion mediated model, shows the critical nucleus changing from 3 to 2 pentacene for Ek>5-6 eV. Optimal conditions to produce single crystalline films are envisaged. 相似文献
986.
In an optical fiber link with polarization-dependent loss (PDL), we demonstrate that although the complex polarization mode dispersion vector cannot be fully obtained by the reflectometric measurement, the spectrally resolved differential group delay (DGD) and differential attenuation slope (DAS) can be explicitly determined by such measurements performed simultaneously in the optical frequency domain and the fiber length domain. In principle, this technique can be used to realize the spectrally resolved and spatially resolved measurement of DGD and DAS in an optical fiber link having PDL based on distributed Rayleigh backscattering. We report the experimental result based on the far-end Fresnel reflection to confirm the validity of the proposed method. 相似文献
987.
We introduce a way to estimate the fluctuation of the refractive index during thin film deposition, through an optical monitor. The thicknesses and error-compensated thickness for each layer are analyzed. A novel monitoring method is thereby derived. The revised refractive index and the choice of highly sensitive monitoring wavelengths help us predict the termination points more accurately. The performance of a narrow-bandpass filter monitored by this method is demonstrated. 相似文献
988.
We experimentally demonstrate cavity linewidth control by manipulating dispersion of the intracavity medium. By making use of the dramatic change of Kerr nonlinearity near electromagnetically induced transparency resonance in a three-level atomic system, the cavity transmission linewidth can be greatly modified. As the cavity input intensity increases, the cavity linewidth changes from below to above empty cavity linewidth, corresponding to subluminal and superluminal photon propagation in the cavity, respectively. 相似文献
989.
Exact solutions for KdV system equations hierarchy are obtained by using the inverse scattering transform. Exact solutions of isospectral KdV hierarchy, nonisospectral KdV hierarchies and τ-equations related to the KdV spectral problem are obtained by reduction. The interaction of two solitons is investigated. 相似文献
990.
Chao Rong Wu Yan-Wei Lu Ling Xu Wei-Feng Wang Chang-Yun Shao Chang-Lun 《Chemistry of Natural Compounds》2021,57(2):343-345
Chemistry of Natural Compounds - Benzomalvins B, C, and E (1, 2, and 3) were simultaneously obtained from the marine fungus Aspergillus sp. isolated from the soft coral Sinularia sp., collected... 相似文献