Josephson dynamics for coupled polariton modes under the atom–field interaction in the cavity

We consider a new approach to the problem of Bose–Einstein condensation (BEC) of polaritons for atom–field interaction under the strong coupling regime in the cavity. We investigate the dynamics of two macroscopically populated polariton modes corresponding to the upper and lower branch energy states coupled via Kerr-like nonlinearity of atomic medium. We found out the dispersion relations for new type of collective excitations in the system under consideration. Various temporal regimes like linear (nonlinear) Josephson transition and/or Rabi oscillations, macroscopic quantum self-trapping (MQST) dynamics for population imbalance of polariton modes are predicted. We also examine the switching properties for time-averaged population imbalance depending on initial conditions, effective nonlinear parameter of atomic medium and kinetic energy of low-branch polaritons. PACS 03.75.Lm; 71.36.+c; 42.50.Fx     

Laser-induced synthesis of metal–carbon materials for implementing surface-enhanced Raman scattering

Metal–carbon materials exhibiting surface-enhanced Raman scattering have been synthesized by laser irradiation of colloidal systems consisting of carbon and noble metal nanoparticles. The dependence of the Raman scattering intensity on the material composition and laser irradiation conditions has been investigated. The possibility of recording the Raman spectrum of organic dye rhodamine 6G, deposited in amount of 10^–6 M on the substrate obtained from a colloidal solution is demonstrated.     

Laser-Induced Nanocluster Thin-Film Systems with Controlled Topology and Composition: The Possibility of Creating Superconducting Structures Based on New Physical Principles

Crystallography Reports - The physical properties of solid structures depending on the boundary conditions in topologically ordered nanocluster systems are discussed. These systems are synthesized...     

Frobenius nonclassicality of Fermat curves with respect to cubics

For Fermat curves F: aX ⁿ + bY ⁿ = Z ⁿ defined over F _q , we establish necessary and sufficient conditions for F to be F _q -Frobenius nonclassical with respect to the linear system of plane cubics. In the new F _q -Frobenius nonclassical cases, we determine explicit formulas for the number N _q (F) of F _q -rational points on F. For the remaining Fermat curves, nice upper bounds for N _q (F) are immediately given by the Stöhr–Voloch Theory.     

SU(3) symmetry operational approach to measuring amplitude and phase parameters for an optical field

We consider a new approach to the SU(3) symmetry polarization in Hilbert space for a quantum-optical Bose system with internal Gell-Mann symmetry. The operational determination of the SU(3) amplitude and phase characteristics for a three-mode optical field is discussed for the first time. An original twelve-port interferometer for simultaneous measurements of both the Gell-Mann and the phase parameters is proposed. The quantum properties of various W-class qutrit states under the measurement procedure for quantum information purposes are examined.     

Optical properties of multilayer bimetallic films obtained by laser deposition of colloidal particles

The optical properties of multilayer bimetallic films composed of silver and gold nanoparticles have been investigated. The dependence of the transmission spectra of the films on their morphology is demonstrated. A finite-difference time-domain (FDTD) simulation has confirmed that there is a dependence of the transmission spectra on the average distance between particles and the number of deposited layers.     

Propagation of Smallness for Harmonic and Analytic Functions in Arbitrary Domains

In this paper the authors develop a new approach to the problemof ‘propagation of smallness’ for harmonic functionsin arbitrary domains, in Rⁿ (n 2). The main result of thispaper is a certain logarithmic-convexity relation for the L²-normsof harmonic functions. As a consequence, new kinds of uniquenessresults for harmonic functions are obtained. The method worksalso for analytic functions in C, with L^p-norms (p > 0).1991 Mathematics Subject Classification 31B05.     

Drop deposition of thin nanostructured coatings of lead telluride

The current-voltage relationships of deposited structures are measured for cluster structures consisting of nanoparticles of lead telluride. Variation in the value of the tunnel current is shown. Optimum conditions for the possible emergence of quantum-hopping conductivity due to carrier tunneling (the characteristic sizes of the nanoclusters and the distances between them) are determined.