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91.
R. Paschotta J. Aus der Au G.J. Spühler F. Morier-Genoud R. H?vel M. Moser S. Erhard M. Karszewski A. Giesen U. Keller 《Applied physics. B, Lasers and optics》2000,70(7):S25-S31
We discuss challenges arising from the quest for high average powers from passively mode-locked diode-pumped lasers. The recently obtained detailed understanding of Q-switching instabilities in passively mode-locked lasers turns out to be a crucial element on the way towards higher powers. We give an overview on results achieved with Nd:YAG (10.7 W, 16 ps and 27 W, 19 ps), Yb:YAG (8.1 W, 2.2 ps and 16 W, 0.7 ps) and Nd:glass (1.4 W, 275 fs). 相似文献
92.
93.
A new type of transition metal nitride, viz. alumina-supported cobalt nitride, was synthesized for the first time by NH3-temperature-programmed reaction, and its structure was characterized by BET, X-ray diffraction (XRD) and X-ray photoelectron spectroscopic (XPS) techniques. The supported cobalt nitride performs much better than its bulk counterpart for NO decomposition, owing to its small crystal size, high thermal stability and big surface area. 相似文献
94.
We show that, in terms of physical observables, transition probabilities in quantum mechanics can be calculated in a truly gauge invariant way, i.e., independent of the choice of gauge and that recent arguments for the preference of a particular gauge are due to misconceptions. 相似文献
95.
96.
97.
C.K. Au 《Physics letters. A》1976,56(3):186-188
We present values of the ground state Lamb shifts of hydrogenic ions obtained non-relativistically without any ultraviolet photon cutoff. The results are in good agreement with existing theoretical values for general Z and the current experimental value for hydrogen. 相似文献
98.
We present an experimental demonstration of the power of feedback in quantum metrology, confirming the predicted [H. M. Wiseman, Phys. Rev. Lett. 75, 4587 (1995)]] superior performance of an adaptive homodyne technique for single-shot measurement of optical phase. For measurements performed on weak coherent states with no prior knowledge of the signal phase, adaptive homodyne estimation approaches closer to the intrinsic quantum uncertainty than any previous technique. Our results underscore the importance of real-time feedback for reaching quantum limits in measurement and control. 相似文献
99.
Andrew T. Au 《合成通讯》2013,43(8):743-748
Cyano-carbonates, conveniently prepared in excellent yields by in-situ trapping of cyanohydrin anions with chloroform[acaron]tes under PTC conditions, have been found to be efficient ketone precursors. 相似文献
100.
Ibsen SD Krause-Nehring J Nachtigall PE Au WW Breese M 《The Journal of the Acoustical Society of America》2011,130(5):3085-3089
A previous comparative analysis of normalized click amplitude spectra from a Tursiops truncatus has shown that those frequencies with the lowest click-to-click variability in spectral content were the frequencies the animal paid attention to during target discrimination tasks. In that case, the dolphin only paid attention to the frequency range between 29-42 kHz which had a significantly higher degree of consistency in spectral content than frequencies above 42 kHz. Here it is shown that despite their morphological and behavioral differences, this same pattern of consistency was used by a Pseudorca crassidens performing a similar discrimination task. This comparison between species provides a foundation for using spectral level variability to determine the frequencies most important for echolocation in rare species and non-captive animals. Such results provide key information for successful management. 相似文献