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We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how
the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection
of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity.
We also show how this scheme can be modified to a teleportation with insurance. 相似文献
23.
Danailov DM Brothers R Viehland LA Johnsen R Wright TG Lee EP 《The Journal of chemical physics》2006,125(8):084309
New experimental measurements are reported for the mobility of O(+) ions in He gas at 300 K. The accuracy of these new values is estimated as +/-2.5%, which allows them to serve as a stringent test of a new ab initio potential that we have calculated using the RCCSD(T) method. We employed the aug-cc-pV5Z basis set with counterpoise corrections and took spin-orbit coupling into account. The present experimental values lie below the calculated ones, but the difference becomes statistically significant only at moderate and high values of the ratio of the electric field strength to the gas number density; even there they are only marginally significant. 相似文献
24.
M.B. Danailov A.A. Demidovich A.N. Kuzmin O.V. Kuzmin V.L. Hait 《Applied physics. B, Lasers and optics》2001,73(7):671-676
Experimental results from studies of the laser characteristics of Nd:LSB crystals in both cw and passive Q-switching arrangements
are presented. The dependence of the main laser parameters on the output coupling and saturable absorber transmission for
two doping levels of Nd was investigated. It is demonstrated that due to its high absorption, low losses and intrinsic strong
thermal lensing, even at pump powers of less than 200 mW, the Nd:LSB has excellent properties in terms of efficiency, beam
quality and pulse duration. In addition, it exhibits high pulse-to-pulse and pulse width versus pump power stability.
Received: 11 June 2001 / Revised version: 30 July 2001 / Published online: 15 October 2001 相似文献
25.
Received: 25 February 1997/Revised version: 20 June 1997 相似文献
26.
采用密度泛函理论计算研究了在铈表面掺杂的过渡金属(TM)离子对表面晶格氧原子活化的影响.为此,测定了经TM离子修饰的CeO2最稳定(111)表面终端的结构和稳定性.除了保持八面体氧配位的锆和铂掺杂剂外, TM掺杂剂在取代表面Ce离子时更倾向于正方形平面配位.除了Pt(1.14 eV)和Zr(正方形平面配位不稳定)外,所有TM掺杂剂的表面结构从八面体到正方形平面都很容易.通常,四价TM阳离子的离子半径比Ce^4+的小得多,从而导致了显著的拉伸应变晶格,并解释了氧空位形成能量的降低.除Zr外,当产生一个氧空位时,优先形成正方形平面结构.热力学分析表明, TM掺杂CeO2表面在典型环境催化条件下存在氧缺陷.一个具有实际意义的例子是锆掺杂CeO2(111)中的晶格氧容易活化,从而有利于CO氧化.研究结果强调了晶格氧活化的本质和TM掺杂剂在TM-铈固溶催化剂中的优选位置. 相似文献
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V. Z. Zubialevich E. V. Lutsenko V. N. Pavlovskii A. L. Gurskii A. V. Danilchyk G. P. Yablonskii M. B. Danailov B. Ressel A. A. Demidovich J. F. Woitok H. Kalisch Y. Dikme R. H. Jansen M. Lünenbürger B. Schineller M. Heuken 《Journal of Applied Spectroscopy》2008,75(1):96-103
With the aim of establishing the mechanisms for spontaneous recombination and lasing, we have studied InGaN/GaN multiple quantum
well heterostructures emitting in the 450 nm region and grown by organometallic vapor-phase epitaxy on silicon substrates
using several mechanical stress-reducing AlN/AlGaN inserts. Photoluminescence (PL) excitation spectroscopy, the non-monoexponential
nonequilibrium carrier relaxation kinetics, and x-ray diffractometry data indicate significant inhomogeneity of the InGaN
solid solution in quantum wells of these structures. The dependences of the position of the photoluminescence spectra on the
excitation level and the temperature, the large shift in the photoluminescence, gain, and lasing spectra relative to the absorption
edge allow us draw the conclusion that the dominant contribution to spontaneous and stimulated recombination comes from nonequilibrium
charge carriers localized in indium-rich InGaN clusters.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 1, pp. 94–101, January–February, 2008. 相似文献
29.
薄壁杆系结构的梁元分析模型 总被引:1,自引:0,他引:1
本文导出了用于薄壁杆系结构弹性分析的薄壁梁元分析模型,在空间梁元分析模型^[3]的基础上,采用了一种改进的位移模式,考察了薄壁杆件可能发生的拉压,剪切,弯曲,扭转和翘曲等各变形形式以及它们的耦合效应,得出了相应的单元形函数,同时从工程应变的定义出发,采用Taylor级数展开的方法,建立了单元的五阶近似正交变表达式,并建立了相应的薄壁单元刚度方程,从而得出了局部坐标系下单元刚度矩阵的显式,根据本文所导出的薄壁梁元分析模型,编制了相应的结构计算程序,通过算例验证了本文所推导的单元刚度矩阵,同时通过与传统空间梁元计算模型计算结果的比较,阐述了截面翘曲对薄壁杆系结构的影响。 相似文献
30.
Comparison of cw laser performance of Nd:KGW, Nd:YAG, Nd:BEL, and Nd:YVO4 under laser diode pumping 总被引:4,自引:0,他引:4
A.A. Demidovich A.P. Shkadarevich M.B. Danailov P. Apai T. Gasmi V.P. Gribkovskii A.N. Kuzmin G.I. Ryabtsev L.E. Batay 《Applied physics. B, Lasers and optics》1998,67(1):11-15
4 crystals under low-power laser diode end-pumping. Output power dependencies on the pump power and the pump wavelength of
these diode-pumped solid state lasers were investigated. The high Nd3+ concentration of the Nd:KGW samples used in our measurements as well as up-conversion and exited-state absorption processes
in Nd:KGW cause the reduced laser output power dependence on the pump wavelength which was experimentally observed. At pump
levels up to 270 mW a slope efficiency of ηsl≈46% was reached for the Nd:KGW laser. Nd:KGW microchip laser operation with a slope efficiency of ηsl≈50% was demonstrated. Thermal lensing in Nd:KGW at pump powers up to 3 W was measured.
Received: 4 August 1997 相似文献