As an extension of the Robinson-Trautman solutions of D = 4 general relativity, we investigate higher dimensional spacetimes which admit a hypersurface orthogonal, non-shearing and expanding geodesic null congruence. Einstein's field equations with an arbitrary cosmological constant and possibly an aligned pure radiation are fully integrated so that the complete family is presented in a closed explicit form. As a distinctive feature of higher dimensions, the transverse spatial part of the general line element must be a Riemannian Einstein space, but it is otherwise arbitrary. On the other hand, the remaining part of the metric is-perhaps surprisingly-not so rich as in the standard D = 4 case, and the corresponding Weyl tensor is necessarily of algebraic type D. While the general family contains (generalized) static Schwarzschild-Kottler-Tangherlini black holes and extensions of the Vaidya metric, there is no analogue of important solutions such as the C-metric.

Through detailed quantum calculations, the presence of classical discrete breathers and, subsequently, a two-phonon bound state (TPBS) or quantum breather (QB) state have already been shown in nonlinear photonic materials such as ferroelectrics. The latter was done in a periodic boundary condition in terms of the variations of TPBS parameters against impurity that is related to nonlinearity. Metamaterials are also nonlinear optical materials for applications as a split-ring-resonator (SRR) in antenna arrays. By using a Klein-Gordon approach, first multi-solitons and classical breathers are shown. For QBs, by using a periodic boundary condition, the variation of the TPBS parameters with coupling within the SRR elements is observed. Finally, in a non-periodic boundary condition approach, the temporal evolution of the number of quanta is shown eventually in order to derive the critical time of redistribution of quanta that is proportional to the QB's lifetime in femtoseconds, which also shows variation with coupling in the SRR system.

This article describes the design of a laser setup excited by 3 He(n,p) 3 H reaction products and intended for investigations of the laser characteristics of 3 He mixtures with metal vapors or other gases at temperatures up to 800°C. This setup could also be used to study the effect of the medium heating on the characteristics of nuclear-pumped gas lasers.

A probabilistic teleportation scheme for atomic state via cavity QED [Phys. Rev. A 70 (2004) 054303] is revisited and accordingly some improvements are made.No cloning theorem forbids a perfect copy of an arbitrary unknown quantum state. How to interchange different resources has ever been a question in quantum computation and quantum information. In 1993, Bennett et al . [1] first presented a quantum teleportation scheme. In the scheme, an arbitrary unknown quantum state in a qubit can be teleported to a distant qubit with the help of Einstein-Podolsky-Rosen (EPR) pair. Their work showed in essence the interchangeability of different resources in quantum mechanics. Hence, after Bennett et al .'s pioneering work in 1993, quantum teleportation has attracted much attention. [2−30] As a matter of fact, one can transfer quantum states ont only by the method of teleportation [1] but also by quantum state transfer (QST). [31−35] Recently QST has attracted some attention and interests continuously increase. [31−39] There are various physical systems that can be used for QST, one of them being the atomcavity system. [31−35] In this paper we will revisit a recently proposed probabilistic teleportation scheme for atomic state via cavity QED [22] and improve it.Let us briefly review the probabilistic teleportation scheme of atomic state proposed by Ye and Guo. [22] Assume that the atom 1 is in a state

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