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排序方式: 共有222条查询结果,搜索用时 15 毫秒
61.
62.
I. P. Christov 《Applied physics. B, Lasers and optics》2005,80(4-5):405-408
The guiding of an attosecond (as) X-ray pulse in a two-dimensional atomic structure is analyzed. The results obtained from a simple model show that an atomic-scale waveguide which consists of a barium monoxide lattice where five rows of atoms have been removed can successfully guide pulses with duration 20 as and wavelength 10 Å. This is attributed to an improved total external reflection in the discrete atomic structure. When the carrier frequency is higher than the plasma frequency, the guide causes minor distortions in the pulse profile. For lower frequencies, the X-ray pulse is significantly affected by the guide dispersion. These results indicate that nano- and sub-nanostructures can be designed for transportation and processing of coherent attosecond-duration electromagnetic pulses, which is important for the newly emerging field of X-ray photonics. 相似文献
63.
T. Miura H. Nagaoka K. Takasago K. Kobayashi A. Endo K. Torizuka M. Washio F. Kannari 《Applied physics. B, Lasers and optics》2002,75(1):19-23
Two mode-locked Ti:sapphire lasers of different wavelengths were precisely synchronized by a simple feedback system employing
sum-frequency generation (cross correlation). When the timing error exceeded the pulse duration, the periodic bunch of the
sum-frequency pulse was used for rough timing adjustment. Using cross correlation with a stretched pulse, we struck a balance
between wide locking range and sensitive timing detection. When the two lasers were well-synchronized, we obtained a continuous
cross-correlation pulse train for 3 min. The holding time of the laser synchronization was extended to over one hour by adding
a motorized stage to the PZT-mounted cavity mirror. We estimated the rms timing jitter between the two lasers by a scanning
cross-correlation measurement. We confirmed that the rms timing jitter of the two lasers during 1.8 s was 28 fs.
Received: 30 January 2002 / Revised version: 14 June 2002 / Published online: 8 August 2002 相似文献
64.
A low-cost multiple-walled carbon nanotubes/polyvinyl alcohol (MWCNTs/PVA) absorber was fabricated by the characteristics of high viscosity in large molecule PVA aqueous solution and vertical evaporation technique. Sandwich structured MWCNT/PVA absorber was constructed by a piece of MWCNT absorber, a piece of round quartz and a piece of reflective mirror. We exploited it to realize Q-switched mode locking operation in a diode-pumped Nd:YVO4 laser. The maximum average output power is about 630 mW. 相似文献
65.
Using the data samples collected at and around the center-of-mass energies of 3.097 GeV and 3. 773 GeV with the BES-Ⅱ detector at the BEPC collider, we select the pure particle samples of muon, electron, kaon and pion, and their mutual (mis)identification rates are also obtained. 相似文献
66.
Direct Measurement of Branching Fraction for Inclusive Semimuonic Decay of Neutral D Mesons
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Using a data sample of about 33pb^-1 collected at and around √s = 3.773 GeV with the BES-Ⅱ detector at the BEPC, we have directly measured the branching fraction for inclusive semimuonic decay of neutral D mesons to be BF(D^0 → μ^+X) = (7.2 ± 1.5 ± 0.8)%. 相似文献
67.
A. A. Sirotkin L. Di Labio A. I. Zagumennyi Yu. D. Zavartsev S. A. Kutovoi V. I. Vlasov W. Lüthy T. Feurer A. A. Onushchenko I. A. Shcherbakov 《Applied physics. B, Lasers and optics》2009,94(3):375-379
The use of glasses doped with PbS nanocrystals as intracavity saturable absorbers for passive Q-switching and mode locking
of c-cut Nd:Gd0.7Y0.3VO4, Nd:YVO4, and Nd:GdVO4 lasers is investigated. Q-switching yields pulses as short as 35 ns with an average output power of 435 mW at a repetition
rate of 6–12 kHz at a pump power of 5–6 W. Mode locking through a combination of PbS nanocrystals and a Kerr lens results
in 1.4 ps long pulses with an average output power of 255 mW at a repetition rate of 100 MHz. 相似文献
68.
69.
Lin Zhang Yunchu Li Muping Song Jeng-Yuan Yang Raymond G. Beausoleil Alan E. Willner 《Applied Physics A: Materials Science & Processing》2009,95(4):1089-1100
Electro-optic modulation plays a critical role in implementing space-, power- and spectrally efficient optical interconnection
for high-capacity computing systems. Microring resonators exhibit a great potential to achieve compact, low power-consumption
and high-speed modulators. In this paper, we briefly review our efforts on designing and analyzing the microring modulators.
Three types of single-ring modulators are discussed, from device behavior to possible system impact. We then present two novel
double-ring modulators in which a passive ring resonator is added, enabling higher operation speed and lower power consumption.
We also describe an opportunity of introducing phase modulation data formats into the on-chip communication environment. In
this paper, our emphasis is placed on linking the devices’ physics to their system performance and providing potential technical
solutions to physical-layer challenges of optical interconnection. 相似文献
70.
Meng Cao Peng Cao Huaijiang Yan Wuguang Lu Fang Ren Yunlong Hu Shuangquan Zhang 《Applied biochemistry and biotechnology》2009,157(3):562-574
Elevated levels of B-cell-activating factor of the tumor necrosis factor family (BAFF) have been implicated in the pathogenesis
of autoimmune diseases in human. In this study, we have constructed a vector for the expression of a novel compact antibody
composed of anti-BAFF single-chain antibody fragment (scFv) and the Fc region (the hinge region, CH2, and CH3 domains) of
human IgG1 in Chinese hamster ovary cells. The scFv–Fc fusion protein, showing spontaneous Fc fragment-mediated homodimerization
via disulfide bridges, was affinity-purified on protein A Sepharose from culture supernatant. The scFv–Fc antibody was demonstrated
to retain high binding affinity to antigen and prolonged clearance time in blood and to possess some human IgG crystallizable
fragment effector functions such as protein A binding and antibody-dependent cellular cytotoxicity. These results suggest
that this recombinant antibody may have therapeutic applications in the therapy of autoimmune disorders mediated by BAFF. 相似文献