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971.
972.
973.
974.
Chih T’sung Shih Zhi Wei Zeng Yin Cheng Chang Yao-Jen Lee Shiuh Chao 《Optical Review》2009,16(4):413-415
We provided a single-mode bent MOS-cross-section rib waveguide design with 0.9 dB/cm bending loss at 25 μm bending radius.
The peak position for the TE-like mode was tuned to the gate oxide around which the maximum amount of free carriers are accumulated
to optimize the free carrier dispersion effect. 相似文献
975.
F. F. Karpeshin M. B. Trzhaskovskaya J. Zhang 《The European Physical Journal A - Hadrons and Nuclei》2009,39(3):341-348
A mechanism of triggering the 12.7keV E3 transition, based on the new decay mode of the 31y isomer via resonance internal conversion and emission of a 1.4keV X-ray
quantum, is considered. Actually, this decay mode was observed previously in the decay of 45- and 46-fold ions of 125Te . For the purpose of triggering, the atomic radiative vertex has to be induced by resonance radiation. This mechanism makes
triggering by an order of magnitude more efficient than triggering a bare nucleus, and is achieved at a lower combination
frequency. An experiment is proposed for the direct observation of the new decay mode. This also offers a new way of resonance
scattering of these X-rays. Triggering through higher-lying 2573 and 2805keV states is also considered. The results are extended
to the general problem of triggering. The main obstacle for enhancing the efficiency is a high internal conversion rate. For
this reason, shape isomers with low multipole order --E1 , M1 , and with a high enough energy of triggering transition are of interest for triggering. The partial ionization of the outer
electrons will also help. The same recommendations hold for triggering isomers in laser-produced plasma. 相似文献
976.
S. Gleyzes A. El Amili R. A. Cornelussen P. Lalanne C. I. Westbrook A. Aspect J. Estève G. Moreau A. Martinez X. Lafosse L. Ferlazzo J. C. Harmand D. Mailly A. Ramdane 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(1):107-111
We study a Fabry-Perot cavity formed from a ridge waveguide on a AlGaAs substrate. We experimentally determined the propagation
losses in the waveguide at 780 nm, the wavelength of Rb atoms. We have also made a numerical and analytical estimate of the
losses induced by the presence of the gap which would allow the interaction of cold atoms with the cavity field. We found
that the intrinsic finesse of the gapped cavity can be on the order of F∼30, which, when one takes into account the losses
due to mirror transmission, corresponds to a cooperativity parameter for our system C∼1. 相似文献
977.
J.?Pe?ina J.?K?epelka J.?Pe?inaJr M.?Bondani A.?Allevi A.?Andreoni 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):373-382
Two strongly-pumped parametric interactions are
simultaneously realized in a single nonlinear crystal in order to
generate three strongly correlated optical fields. By combining
together the outputs of two of the three detectors measuring
intensities of the generated fields, we obtain the joint
photocount statistics between the single field and the sum of the
other two. We apply a microscopic quantum theory developed earlier
to determine the joint photon-number distribution and the joint
quasi-distributions of integrated intensities and prove
nonclassical nature of the three-mode state. Finally, by
performing a conditional measurement on the single field, we
obtain a state endowed with a sub-Poissonian statistics, as
testified by the analysis of the conditional Fano factor. The role
of quantum detection efficiencies in this conditional
state-preparation method is discussed in detail. 相似文献
978.
Q. X. Mu Y. H. Ma L. Zhou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,51(3):375-379
We present a method of generating two-mode single atom
laser based on the nonresonant interaction of a three-level
Λ type atom in a two-mode cavity with three strong classical
driving fields. An analytical solution for this effective dynamics
under the presence of the cavity losses is obtained, which allow us
to analyze the entanglement properties and the photon statistics of
the two cavity modes exactly. It is also shown that the possible
generation of the two-mode entangled coherent states in the
transient regime after the atomic measurement. 相似文献
979.
980.
通过数值计算,分析了纳米光纤的色散特性,并比较了纳米光纤中不同直径和不同材料的色散特性.结果表明:二氧化硅纳米光纤有两个零色散波长,随光纤直径的增大,其色散曲线趋于平坦,零色散波长也随之发生改变;硅光纤只有一个零色散波长,且随着直径的增大,零色散波长向长波方向移动.采用广义非线性薛定谔方程来描述超短激光脉冲在纳米光纤中的传输演化过程,利用分步傅里叶方法求解方程.比较了超短脉冲在光纤不同色散区传输时,色散对超连续谱产生的影响以及脉冲波形的演化.在正常色散区,超连续谱谱宽很窄,而在零色散区和反常色散区则可产生
关键词:
色散
超连续谱产生
非线性光学
纳米光纤 相似文献