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991.
Zhongzhi Zhang Shuigeng Zhou Tao Zou Lichao Chen Jihong Guan 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):259-264
We make a mapping from Sierpinski fractals to a new class
of networks, the incompatibility networks, which are scale-free,
small-world, disassortative, and maximal planar graphs. Some
relevant characteristics of the networks such as degree
distribution, clustering coefficient, average path length, and
degree correlations are computed analytically and found to be
peculiarly rich. The method of network representation can be applied
to some real-life systems making it possible to study the complexity
of real networked systems within the framework of complex network
theory. 相似文献
992.
Chen X Zhang L Zhou K Davies E Sugden K Bennion I Hughes M Hine A 《Optics letters》2007,32(17):2541-2543
Using an optical biosensor based on a dual-peak long-period fiber grating, we have demonstrated the detection of interactions between biomolecules in real time. Silanization of the grating surface was successfully realized for the covalent immobilization of probe DNA, which was subsequently hybridized with the complementary target DNA sequence. It is interesting to note that the DNA biosensor was reusable after being stripped off the hybridized target DNA from the grating surface, demonstrating a function of multiple usability. 相似文献
993.
By employing the self-modulation birefringence difference in a semiconductor optical amplifier (SOA), an improved method is proposed to generate a complete optical single-sideband (OSSB) signal. Over 30 dB sideband suppression ratios (SSRs) of lower OSSB signals are obtained over a 12 dB input power range and a 36 nm wavelength span, with a maximum of over 35 dB. Upper OSSB signals with an SSR of over 15 dB are observed using a SOA for what is believed to be the first time. This method is effective even for the carrier-suppressed signal. The theory for OSSB generation in an SOA is extended and verified by experiment. 相似文献
994.
Schematic design of a complex thin-film luminescent screen usable for vacuum fluorescent and field emission display 总被引:2,自引:0,他引:2
Based on the facts related to solid-state cathodoluminescence, mixed excitation, and serial excitation recently discovered in our laboratory, a fundamental schematic design and a series of different schematic elaborated designs are proposed for protection from electron accumulation, reasonable use of a luminescent screen, and enhancement of light intensity. 相似文献
995.
We report a higher precision measurement of the refractive index of carbon dioxide using a frequency comb as the light source in a Mach-Zehnder interferometer setup. The experimental sensitivity can reach the level of 8.8x10(-9). Taking into account the measurement accuracy of temperature and pressure, the experimental accuracy has a value of 1.2x10(-8). The measurement result has a deviation from the commonly quoted result [Old , J. Opt. Soc. Am.61, 89 (1971)] by 6.4x10(-7) at 800 nm. 相似文献
996.
Peng Wang Xia Wang Youming Chen Guangan Zhang Junyan Zhang 《Applied Surface Science》2007,253(7):3722-3726
Ti-doped hydrogenated diamond-like carbon (DLC) films were deposited on Si(1 0 0) substrates by a filtered cathodic vacuum arc (FCVA) method using Ar and CH4 as the feedstock. The composition and microstructure of the films were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy and IR spectroscopy. The internal stress was determined by the radius of curvature technique. The influence of the bias voltage on the microstructure of the as-deposited films was investigated. It was found that the graphite-like bonds was dominated in the Ti-doped DLC film deposited at 0 V bias voltage. When bias voltage was increased to −150 V, more diamond-like bond were produced and the sp3 content in film reached the maximum value, after which it decreased and more graphite-like bonds feature produced with further increase of the negative bias voltage. The compressive internal in the Ti-doped DLC films also exhibited a maximum value at −150 V bias voltage. IR results indicated that CH bonded intensity reduced, and H atoms bonded with C atoms were substituted for the Ti atoms as the negative bias voltage increasing. All the composition and microstructure change can be explained by considering the plasma conditions and the effect of negative bias voltage applied to the substrate. 相似文献
997.
Photonic generation of a millimeter-wave signal based on sextuple-frequency multiplication 总被引:2,自引:0,他引:2
A millimeter-wave signal with sextuple-frequency multiplication of a microwave source is obtained with two cascaded optical modulators, which are driven by the same microwave source with phase deviation of pi/2 introduced by an electrical phase shifter. Without any optical filter, a wideband continuously tunable millimeter-wave signal is easily generated. 相似文献
998.
Converging-axicon-based radially polarized ytterbium fiber laser and evidence on the mode profile inside the gain fiber 总被引:3,自引:0,他引:3
The radially polarized mode is achieved from an active Yb fiber by utilizing of an intracavity converging axicon, where the axicon acts as a TM(01) mode selector based on not only its Brewster convex surface but also the distance between its vertex and plane output coupler. The polarization state of the annular laser beam is checked by using a home-made eight-hole aperture. Furthermore, an uncoated plane glass plate is inserted into the cavity, and the reflected beam points to the existence of an annular lasing mode inside the gain fiber. The issues for developing high-power radially polarized fiber lasers also are considered. 相似文献
999.
The critical behavior of passive mode locking has been demonstrated in a figure-eight fiber laser that performs rational harmonic mode locking (RHML). On both the repetition rate and the pulse amplitude distribution, the observed pulse trains near the threshold exhibit the same regulations as the rational harmonic mode-locked ones. The theory also shows that there should be a middle status of RHML before achieving normal mode locking. It is important to note that the results provide what we believe to be the first confirmed attempt to address a fundamental question: how does a laser become mode locking with an increase of pump power? 相似文献