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61.
We propose an optical H-tree structure to distribute a clock signal onto 16 electronic chips at 1 Gb/s for a clock skew and timing jitter of less than 100 ps. Fabrication steps and performance results are presented.  相似文献   
62.
63.
We report ultrahigh-sensitivity static strain sensing (noise equivalent strain 相似文献   
64.
Journal of Fluorescence - A new tri-naphthoylated Cyclotriveratrylene molecule has been synthesized for the rapid and sensitive detection of 4-nitrotoluene (4-NT) among various nitro aromatic...  相似文献   
65.
Poly(vinylpyrrolidone)‐stabilized silver nanoparticles deposited onto strained‐silicon layers grown on graded Si1−xGex virtual substrates are utilized for selective amplification of the Si–Si vibration mode of strained silicon via surface‐enhanced Raman scattering spectroscopy. This solution‐based technique allows rapid, highly sensitive and accurate characterization of strained silicon whose Raman signal would usually be overshadowed by the underlying bulk SiGe Raman spectra. The analysis was performed on strained silicon samples of thickness 9, 17.5 and 42 nm using a 488 nm Ar+ micro‐Raman excitation source. The quantitative determination of strained‐silicon enhancement factors was also made. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
66.
We report the use of cross-polarized wave generation to perform both pulse shortening and temporal cleaning of a high-energy ytterbium-doped fiber-based femtosecond laser system. The nonlinear processes allow both a highly efficient nonlinear conversion of 20% and a large compression ratio of 3.5, with inherently improved coherent and incoherent contrasts. This results in the generation of 37 μJ, 115 fs pulses at a repetition rate of 100 kHz with high temporal quality.  相似文献   
67.
Kwee P  Willke B  Danzmann K 《Optics letters》2011,36(18):3563-3565
The power noise of a cw Nd:YAG laser system was measured at radio frequencies using the optical ac coupling technique. An additional mode cleaner in the setup allowed a high optical ac coupling amplification of 62.3. For the first time, to our knowledge, a sensitivity of 1.1×10?1? Hz(-1/2) relative power noise was achieved corresponding to an equivalent detected photocurrent of 32 A. High precision optics experiments can utilize this scheme to improve the sensitivity of their photodetectors.  相似文献   
68.
High-resolution scanning tunneling microscopy (STM) and temperature-programmed desorption (TPD) were used to study the interaction of O2 with reduced TiO2(110)–(1 × 1) crystals. STM is the technique of choice to unravel the relation between vacancy and non-vacancy assisted O2 dissociation channels as a function of temperature. It is revealed that the vacancy-assisted, first O2 dissociation channel is preferred at low temperature (~ 120 K), whereas the non-vacancy assisted, second O2 dissociation channel operates at temperatures higher than 150 K–180 K. Based on the STM results on the two dissociative O2 interaction channels and the TPD data, a new comprehensive model of the O2 chemisorption on reduced TiO2(110) is proposed. The model explains the relations between the two dissociative and the molecular O2 interaction channels. The experimental data are interpreted by considering the available charge in the near-surface region of reduced TiO2(110) crystals, the kinetics of the two O2 dissociation channels as well as the kinetics of the diffusion and reaction of Ti interstitials.  相似文献   
69.
Hexagonal Ba1.20Ca0.8?2x?ySiO4:xCe3+,xLi+,yMn2+ phosphors exhibit two emission bands peaking near 400 and 600 nm from the allowed f–d transition of Ce3+ ions and the forbidden 4T16A1 transition of Mn2+ ions, respectively. The strong interaction between Ce3+/Mn2+ ions is investigated in terms of energy transfer, crystal field effect, and microstructure by varying their concentrations. They show a higher quenching temperature of 250 °C than that of a commercially used (Ba,Sr)2SiO4:Eu2+ phosphor (150 °C). Finally, mixtures of these phosphors with green-emissive Ba1.20Ca0.70SiO4:0.10Eu2+ are tested and yielded correlated color temperatures from 3500 to 7000 K, and color rendering indices up to 95%.  相似文献   
70.
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