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131.
DAIHong-Yi KUANGLe-Man LICheng-Zu 《理论物理通讯》2005,44(1):40-44
We propose a scheme to probabilistically teleport an unknown arbitrary three-level two-particle state by using two partial entangled two-particle states of three-level as the quantum channel. The classical communication cost required in the ideal probabilistic teleportation process is also calculated. This scheme can be directly generalized to teleport an unknown and arbitrary three-level K-particle state by using K partial entangled two-particle states of three-level as the quantum channel. 相似文献
132.
基于文(1)中的单点精细积分方法,对色散方程Ut=aUxxx提出了一种构造高稳定性三层五点(蛙跳)显格式的广义单点精细积分法,文中格式的局部截断误差为O(x^2+h^2),而稳定性条件为|R|≤g(β)(其中g对任意正实数是单调递增函数),同时类格式中最好的。 相似文献
133.
A. V. Akimov A. N. Matveev A. V. Sokolov S. I. Kanorsky N. N. Kolachevsky G. Yu. Pakhutin V. N. Sorokin 《Journal of Russian Laser Research》2004,25(3):239-252
A technique for creating the source of a bichromatic laser field with a stable mean value of the difference frequency is realized. The spectral characteristics of a femtosecond passive mode-locked laser are used in this technique. Such a source operating in the region of 780 nm is created. The possibility of using the phenomenon of coherent population trapping (CPT) in three-level systems of the rare-earth atoms for the development of secondary frequency standards in the optical range is considered. The contributions of the processes affecting the width and contrast of the CPT resonances and defining their attainable Q factors are studied. The prospects of using the experimental technique developed for the spectroscopy of the CPT resonances in samarium and thulium vapors are discussed. 相似文献
134.
135.
Highly Efficient Multiphoton‐Pumped Frequency‐Upconversion Stimulated Blue Emission with Ultralow Threshold from Highly Extended Ladder‐Type Oligo(p‐phenylene)s 下载免费PDF全文
Dr. Lei Guo Dr. King Fai Li Dr. Xiaoqin Zhang Prof. Kok Wai Cheah Prof. Man Shing Wong 《Angewandte Chemie (International ed. in English)》2016,55(36):10639-10644
A series of highly extended π‐conjugated ladder‐type oligo(p‐phenylene)s containing up to 10 phenyl rings with (L)‐Ph(n)‐NPh (n=7–10) or without diphenylamino endcaps (L)‐Ph(n) (n=7 and 8) were synthesized and investigated for their multiphoton absorption properties for frequency upconverted blue ASE/lasing. Extremely large two‐photon absorption (2PA) cross‐sections and highly efficient 2PA ASE/lasing with ultralow threshold were achieved. (L)‐Ph(10)‐NPh exhibits the highest intrinsic 2PA cross‐section of 3643 GM for a blue emissive organic fluorophore reported so far. The record‐high 2PA pumped ASE/lasing efficiency of 2.06 % was obtained by un‐endcapped oligomer, (L)‐Ph(8) rather than that with larger σ2, suggesting that a molecule with larger σ2 is not guaranteed to exhibit higher η2. All of these oligomers exhibit exceptionally ultralow 2PA pumped ASE/lasing thresholds, among which the lowest 2PA pumped threshold of circa 0.26 μJ was achieved by (L)‐Ph(10)‐NPh. 相似文献
136.
Albert Sung Soo Lee Seung‐Sock Choi He Seung Lee Hyeon Yeol Jeon Kyung‐Youl Baek Seung Sang Hwang 《Journal of polymer science. Part A, Polymer chemistry》2012,50(21):4563-4570
A series of inorganic–organic hybrid block copolymers were synthesized via atom transfer radical polymerization using a fully condensed, ladder‐like structured polyphenylsilsesquioxane end‐functionalized macroinitiator. The inorganic portion, ladder‐like polyphenylsilsesquioxane, was synthesized in a one‐batch, base‐catalyzed system, whereas organic hard and soft monomers, styrene, and n‐butyl acrylate, were polymerized and copolymerized on the ends of the linear, inorganic backbone. Synthesized hybrid diblock, triblock, and random copolymers were characterized by 1H NMR, 29Si NMR, gel permeation chromatography, static light scattering, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. Hybrid block copolymers were well‐defined with low polydispersity (<1.4) and exhibited enhanced thermal properties in the form of increased glass transition and degradation onset temperatures over their organic analogues.© 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
137.
Co(NO3)2, N-carbazolyacetic acid and 4,4′-bipyridyl can give rise to a novel coordination polymer [CO2(Cabo)2(NO3)2(4,4′-bipy)2]n using a fritted U-tube. Single crystal X-ray diffraction displays in the complex, each Co(Ⅱ) is six-coordinated by two N atoms from different 4,4′-bipyridyl ligands, two O atoms of the bridge from two N-carbazolyacetic acid and two O atoms of one nitrate anion to form a distorted octahedral. Two O atoms of the carboxyl group act as bridge to link two Co(Ⅱ) atoms. The resulting structure is a ladder polymer. CCDC: 211713. 相似文献
138.
Quantum entanglement in the system of a moving V-type three-level atom interacting with the SU(1,1)-related coherent fields 下载免费PDF全文
In a system with a moving V-type three-level atom interacting with
the SU(1,1)-related coherent fields,
we investigate the entanglement between the moving three-level atom
and the SU(1,1)-related coherent fields by
using the quantum-reduced entropy, and that
between the SU(1,1)-related
coherent fields by using the quantum relative
entropy of entanglement. It is shown that the two kinds of entanglement
are dependent on the atomic motion and
exhibit the periodic evolution with a
period of 2π/p. The maximal atom--field qutrit entanglement
state can be prepared, and the entanglement preservation
of the SU(1,1)-related coherent fields
can be realized in the interacting process
via the appropriate selection of system
parameters and interaction time. 相似文献
139.
In this paper, we present decoupling bang-bang operations for the suppression of general decoherence, both amplitude and phase damping,
in a three-level system in Λ-configuration. We give a program
to design a sequence of periodic twinborn pulses to suppress the decoherence in such the system. 相似文献
140.
主要研究超冷铯Rydberg原子阶梯型三能级系统的Autler-Townes(A-T)分裂.铯原子基态6S_(1/2)、第一激发态6P_(3/2)和Rydberg态形成阶梯型三能级系统,强耦合光共振作用于6P_(3/2)(F′=5)→34D_(5/2)的跃迁,探测光由偏振光谱锁定在6S_(1/2)(F=4)→6P_(3/2)(F′=5)的跃迁,并由双通的声光调制器在其共振跃迁附近扫描,形成的Rydberg原子A-T分裂谱由单光子计数器探测.A-T光谱的双峰间距与耦合光的拉比频率成正比,实验结果与理论计算在耦合光拉比频率Ω_c2π×9 MHz时符合得很好,在拉比频率Ω_c2π×9 MHz时,测量的A-T分裂比理论计算值小13%.产生偏差的主要原因是由于较大的耦合光拉比频率Ω_c增加了激发的Rydberg原子数,Rydberg原子间的相互作用产生了较大的退相干率所致. 相似文献