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101.
We demonstrate a mode-locked, erbium-doped fiber laser with its repetition frequency synchronized to a second fiber laser via an intracavity electro-optic modulator (EOM). With servo control from the EOM (bandwidth approximately 230 kHz) and a slower speed intracavity piezoelectric transducer (resonance at approximately 20 kHz), we demonstrate stabilization of the repetition frequency with an in-loop rms timing jitter of 10 fs, integrated over a bandwidth from 1 Hz to 100 kHz. This represents what is to our knowledge the first time an EOM has been introduced inside a mode-locked laser cavity for fast servo action and the lowest timing jitter reported for a mode-locked fiber laser. 相似文献
102.
Fei Ye Toshiyuki Mori Ding Rong Ou Alastair N. Cormack 《Solid State Ionics》2009,180(20-22):1127-1132
Defect clusters in several rare-earth-doped ceria (doped with Y, Sm, Gd, Dy and Yb) containing up to four oxygen vacancies and eight dopant cations have been simulated and compared. In all doped ceria systems, the binding energy of the clusters increases with increasing cluster size and the oxygen vacancies tend to form curved chains in the clusters. Moreover, the capability of the growth of defect cluster is affected by dopant type, which can explain the dopant type dependency of domain development with increasing doping concentration in heavily doped ceria. 相似文献
103.
In this paper we study necessary optimality conditions for nonsmooth optimization problems with equality, inequality and abstract set constraints. We derive the enhanced Fritz John condition which contains some new information even in the smooth case than the classical enhanced Fritz John condition. From this enhanced Fritz John condition we derive the enhanced Karush–Kuhn–Tucker condition and introduce the associated pseudonormality and quasinormality condition. We prove that either pseudonormality or quasinormality with regularity on the constraint functions and the set constraint implies the existence of a local error bound. Finally we give a tighter upper estimate for the Fréchet subdifferential and the limiting subdifferential of the value function in terms of quasinormal multipliers which is usually a smaller set than the set of classical normal multipliers. In particular we show that the value function of a perturbed problem is Lipschitz continuous under the perturbed quasinormality condition which is much weaker than the classical normality condition. 相似文献
104.
Xu Chun Song E. Yang Rong Ma Hai Fang Chen Zhong Li Ye Min Luo 《Applied Physics A: Materials Science & Processing》2009,94(1):185-188
ZnWO4 nanorods with a bundle-like structure were synthesized at 180°C for 12 h by a hydrothermal technology from Na2WO4⋅2H2O and ZnSO4⋅7H2O in the presence of sodium dodecyl sulfate (SDS). The as-synthesized bundle-like structure of ZnWO4 nanorods was characterized by various techniques: TEM, XRD and EDS. The luminescence properties of the bundle-like structure
of the ZnWO4 nanorods were investigated by photoluminescence (PL) spectroscopy. 相似文献
105.
We propose a scheme to generate multiple-atom entangled states in separate cavities. In our scheme, only weak cross-Kerr mediums,
homodyne measurement, and some linear elements are employed. With the help of homodyne measurement, four-atom GHZ state can
be obtained with high probability and fidelity, and the proposal can be easily scaled to prepare multiple-atom GHZ state.
Under ideal conditions, the success probability will not be affected by atomic numbers. 相似文献
106.
Recently,self-sustained oscillatory genetic regulatory networks(GRNs) have attracted significant attention in the biological field.Given a GRN,it is important to anticipate whether the network could generate oscillation with proper parameters,and what the key ingredients for the oscillation are.In this paper the ranges of some function-related parameters which are favorable to sustained oscillations are considered.In particular,some oscillatory motifs appearing with high-frequency in most of the oscillatory GRNs are observed.Moreover,there are some anti-oscillatory motifs which have a strong oscillation repressing effect.Some conclusions analyzing these motif effects and constructing oscillatory GRNs are provided. 相似文献
107.
108.
Multichannel and omnidirectional transmission can be realized in one-dimensional periodic metamaterial layers, where double-negative materials and single-negative materials are alternately stacked. The proposed structures can produce as many resonance transmission modes as desired by adjusting the number of the periods. Such transmission modes with perfect transmission are robust against incident angles and polarizations. The frequencies and frequency intervals of these modes can be tuned by changing the thicknesses of the metamaterial layers. Composite right/left-handed transmission lines with lumped elements (capacitors and inductors) were used to verify the characteristics of the considered system. Our findings provide an efficient way to select useful multiple channel signals from all directions, and it is useful in optoelectronic device applications. 相似文献
109.
毛细管电泳法分离联萘酚对映体 总被引:4,自引:1,他引:4
利用新的手性选择剂苄基氯化辛可宁,在非水相中成功地分离了联萘酚的对映体,并对分离的机理作了初步地探讨。 相似文献
110.