Electromagnetically induced transparency via adiabatic following of the nonabsorbing state

It is shown that the adiabatic following of the dark, nonabsorbing state improves significantly the electromagnetically induced transparency performance and slows down the group velocity of the probe pulse. This concept can be used for fast selective gating of one pulse out of a pulse train.     

Quantum information splitting of a two-qubit Bell state using a four-qubit entangled state

A scheme is proposed for quantum information splitting of a two-qubit Bell state by using a four-qubit entangled state as a quantum channel. In the scenario, it is supposed that there are three legitimate parties, say Alice, Bob and Charlie. Alice is the sender of quantum information. Bob and Charlie are two agents. Alice first performs GHZ state measurement and tells Bob and Charlie the measurement results via a classical channel. It is impossible for Bob to reconstruct the original state with local operations unless help is obtained from Charlie. If Charlie allows Bob to reconstruct the original state information, he needs to perform a single-qubit measurement and tell Bob the measurement result. Using the measurement results from Alice and Charlie, Bob can reconstruct the original state. We also consider the problem of security attacks. This protocol is considered to be secure.     

用多粒子态进行量子信息分配

我们提出一个用五粒子态将量子信息分裂成几部分的方案。在这个过程中,如果且只有接受者相互合作才能重建初始比特的态。我们所用的量子通道是Bell太和三比特GHZ态的组合态,这些态在实验上都是很容易制备的。这个方案对某些窃听攻击来说是安全的。而且,它还可以用来实现控制的量子隐形传态。     

用多粒子态进行量子信息分配

我们提出一个用五粒子态将量子信息分裂成几部分的方案.在这个过程中,如果有且只有接受者相互合作才能重建初始比特的态.我们所用的量子通道是Bell态和三比特GHZ态的组合态,这些态在实验上都是很容易制备的.这个方案对某些窃听攻击来说是安全的.而且,它还可以用来实现控制的量子隐形传态.     

Deterministic quantum teleportation and information splitting via a peculiar W-class state

In the paper ({\em Phys. Rev.} 2006 A {\bf 74} 062320) Agrawal {\em et al}. have introduced a kind of W-class state which can be used for the quantum teleportation of single-particle state via a three-particle von Neumann measurement, and they thought that the state could not be used to teleport an unknown state by making two-particle and one-particle measurements. Here we reconsider the features of the W-class state and the quantum teleportation process via the W-class state. We show that, by introducing a unitary operation, the quantum teleportation can be achieved deterministically by making two-particle and one-particle measurements. In addition, our protocol is extended to the process of teleporting two-particle state and splitting information.     

The beam splitting in the photonic crystal at a degenerate state

In this paper, using the plane-wave expansion and finite difference time-domain methods, the photons behavior in the photonic crystal is investigated. Theoretically, when a polarized wave is incident from the background medium to the photonic crystal, the beam propagation directions in the photonic crystal determined by two methods are approximately same. But in this paper, the results exhibit that there is an additional direction obtained by the finite difference time-domain method compared with the plane-wave expansion. Considering basic physical mechanism of the photon behavior, the present work circumvents the electromagnetic field distribution in the photonic crystal at a degenerate state, which can reasonably explain the phenomenon. Finally, it shows that a photonic crystal can be properly designed to achieve double refraction simultaneously at one frequency, which can also offer new thoughts and foundation for the novel beam splitter that applied to many optical systems.     

Propagation and scattering of waves in a strongly nonuniform nonabsorbing medium

Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 32, No. 3, pp. 307–313, March, 1989.     

Ortho-para splitting of the exciton ground state in a strong magnetic field

Exciton spectra in bulk semiconductor in strong magnetic fields were studied in the two-band Dirac model. An expression for the energy of ortho-para splitting of the ground state was derived.     

Scattering behavior of nonabsorbing metallic nanoparticles

The optical property of nanosized metallic particles is unique and size-dependent, which cause color variation. In this work, the relationship between diameter and refractive index of nonabsorbing metallic nanoparticles and their scattering properties is studied by using Mie theory. Obtained results indicate that the optical scattering of metallic nanoparticle depends on their refractive index and diameter. The effect of refractive index on optical scattering depends on the nanoparticle diameter. So that, for very fine nanoparticle (10 nm diameter) the effect of refractive index on scattering is not significant. But the effect of refractive index of large size nanoparticle (700–900 nm diameter) on their optical scattering is higher than fine and medium size nanoparticles. The wavelength with maximum scattering depends on refractive index and nanoparticles diameter. In addition, the colorimetric study indicates that the color of nanoparticle depends on their size and refractive index. So that, the lightness, hue, and colorfulness of nanoparticles is changed by changing size and refractive index.     

On the configurational splitting of strangeness analog state

Signatures and behaviour of s^–1s configurations are qualitatively discussed. Suppression of baryon-decay channels and an enhancement of cluster-decay channels are the relevant signals. The hypernuclear-quanta from constitute a novel example of the decay of s^–1 s^–1s configuration.Dedicated to the memory of M. Gmitro.We dedicate this article to our colleague and friend Dr. Marian Gmitro, whose premature death brought a profound grief upon our community. During years, his activities and knowledge in meson-nuclear physics have been very helpful in further development of hypernuclear physics. Also, his role in an efficient topical collaboration between Soviet and Czechoslovak physicists is to be greatly acknowledged.     

Maximum coefficient of light extinction in a nonabsorbing dispersive medium

The maximum value of the light extinction coefficient μ, which can be observed in a dispersive medium with a relative refractive index n of the scattering particles, is studied within the framework of a quasi-crystalline approximation for nonabsorbing dispersive media consisting of monodisperse spherical scatterers. A change in the diffraction parameter x of the scattering particles and their volume concentration c _v is accompanied by nonmonotonic variations of the extinction coefficient, and the function μ(x, c _v ) exhibits several maxima. The dimensions and concentrations of particles are determined, for which the extinction coefficient reaches the absolute maximum μ^max. The μ^max value exhibits a monotonic growth with increasing relative refractive index n of the scattering particles. The conditions of validity of the Ioffe-Regel criterion of radiation localization have been studied. It is established that the localization in nonabsorbing dispersive media can be observed only for n ? 2.7. The intervals of x and c _v in which the criterion of radiation localization is satisfied in dispersive media consisting of particles with n = 3.0 and 3.5 are determined.     

对被囚禁原子质心运动基态波包的有效分束

文章简要地介绍了原子干涉现象及原子光学的发展历史和现状.在对各种不同的原子干涉仪工作原理进行简单总结之后,文章描述了包括文章作者在内的研究小组一项最新的理论工作. 这个工作提出了一个对被囚禁原子质心运动基态波包进行有效分束的物理方案.     

对被囚禁原子质心运动基态波包的有效分束

文章简要地介绍了原子干涉现象及原子光学的发展历史和现状．在对各种不同的原子干涉仪工作原理进行简单总结之后，文章描述了包括文章作者在内的研究小组一项最新的理论工作．这个工作提出了一个对被囚禁原子质心运动基态波包进行有效分束的物理方案．     

Minimal classical communication and measurement complexity for quantum information splitting of a two-qubit state

We investigate the usefulness of the highly entangled five-partite cluster and Brown states for the quantum information splitting (QIS) of a special kind of two-qubit state using remote state preparation. In our schemes, the information that is to be shared is known to the sender. We show that, QIS can be accomplished with just two classical bits, as opposed to four classical bits, when the information that is to be shared is unknown to the sender. The present algorithm, demonstrated through the cluster and Brown states is deterministic as compared to the previous works in which it was probabilistic.     

Simpler criterion on W state for perfect quantum state splitting and quantum teleportation

A simpler criterion is presented to judge whether a W state can be taken as quantum channel for perfectly splitting or teleporting an arbitrary single-qubit state. If the W state is usable, the detailed manipulations in the two quantum information processes are amply shown. Moreover, some relevant discussions are made.     

On the splitting of the exciton ground state in silicon

The exciton ground state in silicon is calculated taking into accoun the effect of the split-off valence band. We show that this effect is very important. The anisotropy splitting of the ground state is found to be 0.32 meV, while a previous analysis, which neglected the split-off band, gave 0.46 meV. The new result is in good agreement with recent experimental data.     

Dispersive solutions of the linear wave equation for a nonabsorbing dispersion-free unbounded medium

The existence of non-one-dimensional nondispersive and dispersive solutions of the “classical” linear wave equation is discussed and substantiated. Procedures for finding the two classes of solutions are formulated, and examples of using these procedures are presented.