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51.
52.
Ultrahigh-resolution optical coherence tomography using continuum generation in an air-silica microstructure optical fiber 总被引:14,自引:0,他引:14
Hartl I Li XD Chudoba C Ghanta RK Ko TH Fujimoto JG Ranka JK Windeler RS 《Optics letters》2001,26(9):608-610
We demonstrate ultrahigh-resolution optical coherence tomography (OCT) using continuum generation in an air-silica microstructure fiber as a low-coherence light source. A broadband OCT system was developed and imaging was performed with a bandwidth of 370 nm at a 1.3-mu;m center wavelength. Longitudinal resolutions of 2.5 microm in air and ~2 microm in tissue were achieved. Ultrahigh-resolution imaging in biological tissue in vivo was demonstrated. 相似文献
53.
Local structure theory calculations7 are applied to the study of cellular automata on the two-dimensional hexagonal lattice. A particular hexagonal lattice rule denoted (3422) is considered in detail. This rule has many features in common with Conway'sLife. The local structure theory captures many of the statistical properties of this rule; this supports hypotheses raised by a study ofLife itself(6). As inLife, the state of a cell under (3422) depends only on the state of the cell itself and the sum of states in its neighborhood at the previous time step. This property implies that evolution rules which operate in the same way can be studied on different lattices. The differences between the behavior of these rules on different lattices are dramatic. The mean field theory cannot reflect these differences. However, a generalization of the mean field theory, the local structure theory, does account for the rule-lattice interaction. 相似文献
54.
Kim YK Auchincloss P Blanis D Bodek A Budd H Eno S Fry CA Harada H Ho YH Kumita T Mori T Olsen SL Shaw NM Sill A Thorndike EH Ueno K Zheng HW Imlay R Kirk P Lim J McNeil RR Metcalf W Myung SS Cheng CP Gu P Li J Li YK Mao ZP Xu YT Zhu YC Abashian A Gotow K Hu KP Low EH Mattson ME Piilonen L Sterner KL Lusin S Rosenfeld C Wang AT Wilson S Frautschi M Kagan H Kass R Trahern CG Breedon RE Kim GN Ko W Lander RL Maeshima K Malchow RL Smith JR Stuart D Williams MC Abe K Fujii Y Higashi Y Kim SK 《Physical review letters》1989,63(17):1772-1775
55.
56.
Entropic entanglement measures of a two-dimensional system of two Coulombically interacting particles confined in an anisotropic harmonic potential are discussed in dependence on the anisotropy and the interaction strength. The harmonic approximation appears exact in the strong interaction limit, allowing determination of the asymptotic expression for the linear entropy. Entanglement properties are dramatically influenced by the anisotropy of the confining potential in the strong-correlation regime. 相似文献
57.
Rypina II Brown MG Beron-Vera FJ Koçak H Olascoaga MJ Udovydchenkov IA 《Physical review letters》2007,98(10):104102
Hamiltonian systems that locally violate the twist condition arise in many applications. Numerical simulations reveal that, when systems of this type are perturbed, the degenerate or nontwist tori are remarkably stable. This phenomenon, which we refer to as strong Kolmogorov-Arnold-Moser (KAM) stability, is shown to be linked to very small resonance widths near degenerate tori. Quantitative estimates of degenerate resonance widths are derived and bifurcations of degenerate resonances are described. Strong KAM stability leads to robust transport barriers, which are important in all of the many applications in which Hamilitonians with the nontwist property arise. 相似文献
58.
Vasilieva T. M. Vasiliev M. N. Garaeva V. V. Zlobin I. S. Mint Zaw Ye Htau Khin Maung Kyaw Htet Wai Yan Zaw Htet Ko Ko 《Russian Physics Journal》2020,62(11):2092-2100
Russian Physics Journal - Different schemes and designs of generators of low-temperature hybrid plasma produced by simultaneous ionization of plasma-generating medium by an electron beam with... 相似文献
59.
Pfeifer P Aston L Banks M Barker S Burress J Carter S Coleman J Crockett S Faulhaber C Flavin J Gordon M Hardcastle L Kallenborn Z Kemiki M Lapilli C Pobst J Schott R Shah P Spellerberg S Suppes G Taylor D Tekeei A Wexler C Wood M Buckley P Breier T Downing J Eastman S Freeze P Graham S Grinter S Howard A Martinez J Radke D Vassalli T Ilavsky J 《Chaos (Woodbury, N.Y.)》2007,17(4):041108
60.
Young-Ho Ko Min-Wook Oh Jae Ki Lee Su-Dong Park Kwang-Joo Kim Yoon-Soo Choi 《Current Applied Physics》2014,14(11):1538-1542
The crystal structure of AgSbTe2 has been refined using first-principles calculations, from which the ordering of the cations, Ag and Sb, was confirmed. The spontaneous formation of two (D4 and L11) phases at ambient and elevated pressure was demonstrated theoretically. The compound was also prepared and its high-pressure structural deformation sequence, ranging from ambient to 50.9 GPa, was observed with synchrotron radiation at room temperature. The compound underwent a pressure-induced amorphization (PIA) at 24.6 GPa and then started recrystallizing at 49.2 GPa. The bulk modulus (B0) and pressure derivative of the bulk modulus (Bp) were determined experimentally to be 56.3 ± 5.1 GPa and 4.3 ± 0.8, respectively. We suggest that large displacements of Te atoms to Ag vacancy positions are responsible for PIA and the recrystallization. 相似文献