We observed optical gain as great as 30 with nearly distortion-free beam propagation in optically dense sodium vapor, using four-wave mixing. Moreover, 15-dB classical noise correlations were seen in the amplified probe and conjugate beams. To achieve this performance in such a strongly absorbing medium, one must suppress unwanted absorption and self-focusing effects. This is accomplished with ...

We consider the photoacoustic effect for multiply scattered light in a random medium. Within the accuracy of the diffusion approximation to the radiative transport equation, we present a general analysis of the sensitivity of a photoacoustic wave to the presence of one or more small absorbing objects. Applications to tumor detection by photoacoustic imaging are suggested.

Conductive-radiative heat transfer in a scattering and absorbing medium bounded by two reflecting and radiating plane surfaces is examined. P1 approximation (diffusion model) is used for the simplification of the original problem. The existence and uniqueness of solutions of the diffusion model are proved. The convergence of an iterative procedure of finding the solution is proved. Numerical ex...

We report the first experimental test of an analytic image reconstruction algorithm for optical tomography with large data sets. Using a continuous-wave optical tomography system with 10(8) source-detector pairs, we demonstrate the reconstruction of an absorption image of a phantom consisting of a highly scattering medium containing absorbing inhomogeneities.

The paper addresses the effects of Soret on unsteady free convection flow of a viscous incompressible fluid through a porous medium with high porosity bounded by a vertical infinite moving plate under the influence of thermal radiation, chemical reaction, and heat source. The fluid is considered to be gray, absorbing, and emitting but non-scattering medium, and Rosseland approximation is consid...

We extend our approach to the Casimir effect between absorbing dielectric multilayers [M. S. Tomaš, Phys. Rev. A 66, 052103 (2002)] to magnetodielectric systems. The resulting expression for the force is used to numerically explore the effect of the medium dispersion on the attractive/repulsive force in a metal-magnetodielectric system described by the Drude-Lorentz permittivities and permeabil...

Conductive-radiative heat transfer in a scattering and absorbing medium bounded by two reflecting and radiating plane surfaces is considered. A diffusion model for describing heat transfer is examined. The theorems of existence and uniqueness of a solution of this problem are proved. An iterative procedure for solving radiative-conductive heat transfer problem is proposed.

Technology spillover from trade channel is important. Absorbing foreign technology by the channel of importation and using the latent technology in those products create export development, increase the quality and quantity of manufactured goods, and modify management, technology improvements and production of goods with high added value; this might favorise optimal allocation of resources. Imp...

Spatio-temporal dynamics of excitable media with discrete three-level active centers (ACs) and absorbing boundaries is studied numerically by means of a deterministic three-level model (see S. D. Makovetskiy and D. N. Makovetskii, http://arxiv.org/abs/cond-mat/0410460 ), which is a generalization of the Zykov-Mikhailov model (see Sov. Phys. – Doklady, 1986, Vol.31, No.1, P.51) for the case of t...