PACS. 64.70M -Transitions in liquid crystals. PACS. 61.25H -Macromolecular and polymer solutions (solubility, swelling, etc.); polymer PACS. 68.42 -Surface phase transitions and critical phenomena. melts.Abstract. -The confinement of, liquid crystalline polymers dissolved in a nematic solvent is analysed using a mean-field theory. For homeotropic anchoring the confinement triggers a tilting phase transition. The transition is reminiscent of the Frederiks transition, however it may be either first or second order.

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PACS. 61.20Gy -Theory and models of liquid structure. PACS. 64.60Ht -Dynamic critical phenomena. PACS. 64.60Kw -Multicritical points.Abstract. -We study the time evolution of an N-component model of bicontinuous microemulsions based on a time-dependent Ginzburg-Landau (GL) equation quenched from a high-temperature uncorrelated state to the low-temperature phases. The behaviour of the dynamical structure factor @k, t ) is obtained, in each phase, in the framework of the large-N limit with both conserved (COP) and non-conserved (NCOP) order parameter dynamics. At zero temperature the system shows multiscaling in the unstructured region up to the tricritical point for the COP, whereas ordinary scaling is obeyed for NCOP. In the structured phase, instead, the conservation law is found to be irrelevant and the form 6 ( k , t )tu/"( Ikk, It'''), with a = 1 and z = 2, is obtained in every case. Simple scaling relations are also derived for the structure factor as a function of the final temperature of the thermal bath. 8 Les Editions de Physique

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PACS. 42.50.Dv -Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements. PACS. 03.65.Ta -Foundations of quantum mechanics; measurement theory.Abstract. -We consider a realistic model for the one-atom micromaser consisting of a cavity maintained in a steady state by the streaming of two-level Rydberg atoms passing one at a time through it. We show that it is possible to monitor the robust entanglement generated between two successive experimental atoms passing through the cavity by the control decoherence parameters. We calculate the entanglement of formation of the joint two-atom state as a function of the micromaser pump parameter. We find that this is in direct correspondence with the difference of the Shannon entropy of the cavity photons before and after the passage of the atoms for a reasonable range of dissipation parameters. It is thus possible to demonstrate information transfer between the cavity and the atoms through this set-up.c EDP Sciences 1 √ 2 (|e + |g ) to |g and the other one to |e . These resultant states may now be detected, and the corresponding outcomes used to signify the states emanating from the cavity.