LPHYS'13.    Plenary Speakers:

  1. Interpretation of Quantum Nonlocality by Weyl's Conformal Geometrodynamics

    Abstract:

    The problem of quantum entanglement of two spin-1/2 particles is faced in a conformally invariant geometric framework. The configuration space of the two particles is extended by adding orientational degrees of freedom and quantum effects, including entanglement, are derived from the conformal curvature of this space. A mechanism is proposed where the space curvature and the particle motion are in mutual interaction and it is proved that this feedback between geometry and dynamics reproduces all quantum features of the two-particle system. Entanglement, in particular, originates from the residual nonlocal interaction among the orientational degrees of freedom of the two spinning, particles.

  2. On the Threshold of Petaera

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      Evgueni M. Dianov


      Fiber Optics Research Center, Russian Academy of Sciences, Moscow, Russia
    Abstract:

    This report briefly describes the evolution of means of communication. The main attention is given to the development of optical communication systems, to optical fiber communication in particular. The state of art of modern optical fiber communication systems is presented. It is shown that the bit rate of these systems is limited to the values of ~100 tb/s through one fiber. The ways to reach the P b/s transmission through one fiber are discussed.

  3. The Organic Artificial Retina Project

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      Guglielmo Lanzani


      Center for Nano Science and Technology @ PoliMi, Istituto Italiano di Tecnologia, Milano, Italy
    Abstract:

    This talk introduces the use of organic semiconductors as artificial photoreceptors in bio mimetic devices. The research started some years ago by demonstrating that organic semiconductors can be used to reproduce the natural retina photoreceptor spectral response in standard photo-diodes. Second step was the development of hybrid solid liquid photodiodes that can naturally interface with a biological environment through the electronic/ionic interface. The next step was demonstrating that primary neurons (from rat brain) grown on top of a photovoltaic semiconducting polymer acquire light sensitivity. This occurs through a specific mechanism of cell stimulation by polymer photoexcitation (CSP) that will be discussed in the presentation. We then studied explanted retinas put in contact with our organic device. We will show that blind retinas, i.e. retinas with severe damage of the photoreceptors, do regain light sensitivity, as demonstrated by ganglion cell electrical activity upon illumination. The process, its relation to CSP, perspective and future developments will be discussed.

  4. Filamentation of Femtosecond Laser Pulses: Recent Advances

    Abstract:

    We review recent developments in the field of femtosecond laser filamentation.

  5. High Power Laser Science at the Extreme Light Infrastructure ELI

    Abstract:

    The Extreme Light Infrastructure ELI will be the world's first international user facility for the scientific laser community. It is part of the ESFRI Roadmap for Pan-European Research Infrastructures of high priority, and it is presently being constructed as a de-centralized facility in the Czech Republic, Hungary and Romania. ELI will be instrumental for establishing and exploiting new scientific communities in the host countries and their neighboring regions, apart from being open to access by an international user community. ELI's innovative funding model utilizes European Regional Development Funds (ERDF) for construction, and - most likely - an European Research Infrastructure Consortium (ERIC) of participating countries for operation. Investment costs are presently estimated at about 850 M€, not including ELI's yet to be decided fourth pillar.

    The recently founded ELI-DC International Association will promote the sustainable development of ELI as a unified pan-European research infrastructure, support the coordinated implementation of the ELI research facilities, and preserve the consistency and complementarity of their scientific missions. It will also organise the establishment of the international ERIC consortium in charge of the future operation of ELI. The Association is open to membership from intersted countries.

    ELI will be dedicated to the fundamental study of laser-matter interaction in the intensity regime I > 1023 W/cm2, and even higher in ELI's forthcoming fourth pillar. Technology is based on chirped pulse amplification of fs optical pulses in broadband solid state laser materials and (or) nonlinear crystals. Single laser beam peak-power will exceed 10 PW, diode pumping will allow for up to 10Hz operation at the multi-PW level. Most of these specifications are at least one order of magnitude above today's top values.

    Besides studying fundamental effects of ultra-strong electro-magnetic forces associated with such intensities ELI will serve to investigate a new generation of compact secondary sources delivering particle and radiation beams of femtosecond to attosecond duration at high energies. Technologies for conversion of laser- into secondary radiation include non-linear frequency conversion in gases, plasmas and on surfaces, laser plasma acceleration of ions and electrons, eventually followed by x-ray generation in periodic magnetic devices, or through laser-driven effects in plasma or vacuum (betatron radiation, Compton backscattering etc.). The planned overall ~10 interaction areas will have ~20 photon and particle beamlines equipped with numerous state-of-the-art experimental stations for an efficient user facility mode of operation enabling multi parallel use and exploitation. ELI will afford wide benefits to society ranging from basic science in physics, natural and life sciences to improvement of oncology treatment, medical and biomedical imaging, fast electronics, materials research and our understanding of aging nuclear reactor materials to development of new methods of nuclear waste processing.

  6. Ultrafast Nanoplasmonics: Toward Coherent Control at the Space-Time Limit

    Abstract:

    Nonadiabatic alignment is a coherent approach to control over the spatial properties of molecules, wherein a short, moderately-intense laser pulse is applied to populate a broad rotational wavepacket with fascinating properties. In the limit of small isolated molecules, nonadiabatic alignment has evolved during the past 17 years into an active field of theoretical and experimental research with a rich variety of applications.

    In the present talk we extend the alignment concept to complex systems, including large polyatomic molecules, dissipative media, nonrigid systems, molecular assembly, molecular conduction junctions and dense molecular ensembles. Following a review of the essential physics underlying alignment, we consider the case of asymmetric top molecules, where alignment overcomes the mechanisms that render the rotations unstable in the classical limit. Next we focus on dissipative media, and illustrate the application of rotational wavepackets as a probe of the decohering properties of the environment. We extend alignment to control the torsional motions of polyatomic molecules, and apply torsional control to manipulate charge transfer events in solutions, suggesting a potential route to light controlled molecular switches. Turning to interfaces, we introduce a route to guided molecular assembly, wherein laser alignment is extended to induce long-range orientational order in molecular layers. Combining the nonadiabatic alignment concept with recent research on nanoplasmonics and on conductance via molecular junctions, we develop an approach to coherent control of transport in the nanoscale. Finally, we explore the case of dense molecular ensembles, where alignment generalizes into a collective phenomenon that gives rise to formation of molecular assembly with long range translational and orientational order, suggesting intriguing potential applications in material design.

  7. Quantum Hydrodynamics and Turbulence in Bose-Einstein Condensates

    Abstract:

    We discuss recent important topics on hydrodynamics and turbulence in quantum fluids. Quantum turbulence was discovered in superfluid 4He in the 1950s. Quantum turbulence is comprised of quantized vortices that are definite topological defects arising from the order parameter appearing in Bose-Einstein condensation. Quantum hydrodynamics and turbulence are still studied actively in superfluid 4He and 3He, but the realization of atomic Bose-Einstein condensation in 1995 has proposed another important stage for this issue. A general introduction to this issue and a brief review of the basic concepts are followed by some recent important developments.

    In the latter half of my talk, I will discuss spin turbulence (ST) in spinor Bose-Einstein condensates focusing on some analogy with spin glass state. ST is characterized by the -7/3 power law in the spectrum of the spin-dependent interaction energy. The direction of the spin density vector is spatially disordered but temporally frozen in ST, showing some analogy with spin glass state. Thus we introduce the order parameter of spin glass into ST in spinor BECs. When ST develops through some instability, the order parameter grows with the appearance of the -7/3 power law, succeeding in describing well ST.

  8. Bose-Einstein Condensation of Photons

    Abstract:

    Bose-Einstein condensation, the macroscopic ground state accumulation of particles with integer spin (bosons) at low temperature and high density, has been observed in several physical systems, including cold atomic gases and solid state physics quasiparticles. However, the most omnipresent Bose gas, blackbody radiation (radiation in thermal equilibrium with the cavity walls) does not show this phase transition. The photon number is not conserved when the temperature of the photon gas is varied (vanishing chemical potential), and at low temperatures photons disappear in the cavity walls instead of occupying the cavity ground state. Here I will describe an experiment observing a Bose-Einstein condensation of photons in a dye-filled optical microcavity. Further, recent experiments investigating the second order coherence of the condensate will be reported. The results give evidence for Bose-Einstein condensation under grandcanonical ensemble conditions, as can be understood from effective particle exchange of condensate photons with dye electronic excitations.