On preparation of the W-states from atomic ensembles

A scheme, where three atomic ensembles can be prepared in the states of the W-class via Raman type interaction of strong classical field and a projection measurement involved three single-photon detectors and two beamsplitters, are considered. The obtained atomic entanglement consists of the Dicke or W-states of each of the ensembles.Comment: 4 pages, 1 figure, minor correction

Improvement of the reverse characteristics of Schottky diodes using gettering

The paper considers the causes and mechanisms of the influence of defects and impurities on the reverse current of the Schottky diode. The influence of two getter regions, which were created by different technologies on the working side and the reverse side of the plate, on the value of the reverse current of diodes was experimentally investigated, and the physical factors of such influence were analyzed. The proposed technology for creating getter regions allows one to significantly reduce the reverse current of diodes and increase the product yield.В настоящей работе исследованы влияние структурных дефектов и примесных загрязнений поверхности на уровень обратных токов ДШ и эффективность применения операций геттерирования для его снижения и повышения выхода годных приборов. Установлено, что причинами низкого процента выхода годных структур ДШ при контроле уровня их обратных токов являются окислительные дефекты упаковки, образующиеся в активных областях диодов в процессе проведения термического окисления, и примесные загрязнения на поверхности диодных структур. Предложена технология изготовления структур ДШ с двумя геттерными областями, одна из которых создана имплантацией аргона на обратной стороне пластины, вторая — диффузией бора на рабочей стороне пластины.У даній роботі досліджено вплив структурних дефектів і домішкових забруднень поверхні на рівень зворотних струмів ДШ і ефективність застосування операцій гетерування для його зниження і підвищення виходу придатних приладів. Встановлено, що причинами низького відсотка виходу придатних структур ДШ при контролі рівня їх зворотних струмів є окислювальні дефекти упаковки, що утворюються в активних областях діодів в процесі проведення термічного окислення, і домішкові забруднення на поверхні діодних структур. Запропоновано технологію виготовлення структур ДШ з двома гетерними областями, одна з яких створена імплантацією аргону на зворотному боці пластини, друга — дифузією бору на робочій стороні пластини

One-way quantum computation via manipulation of polarization and momentum qubits in two-photon cluster states

Four-qubit cluster states of two photons entangled in polarization and linear momentum have been used to realize a complete set of single qubit rotations and the C-NOT gate for equatorial qubits with high values of fidelity. By the computational equivalence of the two degrees of freedom our result demonstrate the suitability of two photon cluster states for rapid and efficient one-way quantum computing.Comment: RevTex4, 4 pages, 3 figure

Quantum teleportation of entangled coherent states

We propose a simple scheme for the quantum teleportation of both bipartite and multipartite entangled coherent states with the successful probability 1/2. The scheme is based on only linear optical devices such as beam splitters and phase shifters, and two-mode photon number measurements. The quantum channels described by multipartite maximally entangled coherent states are readily made by the beam splitters and phase shifters.Comment: 4 pages, no figure

A study of the efficiency of the class of WW-states as a quantum channel

Recently, a new class of $W$-states has been defined by Agarwal and Pati \cite{agarwal} and it has been shown that they can be used as a quantum channel for teleportation and superdense coding. In this work, we identify those three-qubit states from the set of the new class of $W$-states which are most efficient or suitable for quantum teleportation. We show that with some probability $|W_1>=(1/2)(|100>+|010>+\sqrt{2}|001>)$ is best suited for teleportation channel in the sense that it does not depend on the input state.Comment: 7 pages, Late

Squeezing based on nondegenerate frequency doubling internal to a realistic laser

We investigate theoretically the quantum fluctuations of the fundamental field in the output of a nondegenerate second harmonic generation process occuring inside a laser cavity. Due to the nondegenerate character of the nonlinear medium, a field orthogonal to the laser field is for some operating conditions indepedent of the fluctuations produced by the laser medium. We show that this fact may lead to perfect squeezing for a certain polarization mode of the fundamental field. The experimental feasibility of the system is also discussed.Comment: 6 pages, 5 figure

Multipartite entanglement for entanglement teleportation

The scheme for entanglement teleportation is proposed to incorporate multipartite entanglement of four qubits as a quantum channel. Based on the invariance of entanglement teleportation under arbitrary two-qubit unitary transformation, we derive relations of separabilities for joint measurements at a sending station and for unitary operations at a receiving station. From the relations of separabilities it is found that an inseparable quantum channel always leads to a total teleportation of entanglement with an inseparable joint measurement and/or a nonlocal unitary operation.Comment: slightly modifie

Copper-Catalyzed Transformation of Hydrazones into Halogenated Azabutadienes, Versatile Building Blocks for Organic Synthesis

A one-step copper-catalyzed reaction of aldehyde-derived N-substituted hydrazones with CCl4 resulted in efficient synthesis of 4,4-dichloro-1,2-diazabuta-1,3-dienes. It was proven that this C-C bond-forming cascade reaction operates via an addition of trichloromethyl radical to the C=N bond of hydrazone followed by a base-induced elimination of HCl. The reaction was found to be very general, as diverse hydrazones possessing various aromatic groups at N-site, as well as aromatic, aliphatic, and heterocyclic substituents at C-site, are capable partners for coupling with a wide range of polyhalogenated compounds (CCl3Br, CBr4, CCl3CN, CCl3COOEt, CCl3CF3, CBr3CF3) to produce a family of functionalized 1,2-diazabuta-1,3-dienes. It was demonstrated that the prepared heterodienes are highly versatile building blocks for straightforward assembly of various valuable acyclic and heterocyclic molecules. © 2016 American Chemical Society