V. N. Astratov

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Near field optical manipulation of microparticles is usually considered a nonresonant effect determined by the momentum conservation law. In this work we study optical propelling of polystyrene microspheres with diameters from 3 to 20 μm in the evanescent field produced by water immersed tapered microfibers. We show that the velocity of propelling(More)
R. Butté, G. Delalleau, A. I. Tartakovskii, M. S. Skolnick, V. N. Astratov, J. J. Baumberg, G. Malpuech, A. Di Carlo, A. V. Kavokin, and J. S. Roberts Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom(More)
We demonstrate that the super-resolution imaging of a commercial Blu-ray® disk containing a one-dimensional array of 200 nm width stripes separated by 100 nm width grooves can be achieved using high-index microspheres in a liquid environment. By using barium titanate glass microspheres (2-20 μm diameters) with index around 1.9 totally immersed(More)
Recently we showed that light focusing and transport properties of chains of dielectric spheres with D>;>;10λ, where D is the diameter of the sphere and λ is the wavelength, are dominated by periodically focused modes (PFMs) which have extremely small propagation losses. In this work we show that along with a special case of PFMs in(More)
Recent work on strong coupling exciton}polariton phenomena in single and coupled microcavities is presented. We describe experiments for single cavities where the strong coupling nature of the excitations manifests itself. It is also shown that coupled cavities enable optically induced coupling between macroscopically separated exciton states to be(More)
A. I. Tartakovskii, M. Emam-Ismail, R. M. Stevenson, M. S. Skolnick, V. N. Astratov, D. M. Whittaker, J. J. Baumberg, and J. S. Roberts Institute of Solid State Physics, RAS, 142432 Chernogolovka, Russia Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom Toshiba Research Europe Ltd., Cambridge CB4 4WE, United(More)
We show that high index (~2.0) barium titanate glass microspheres are perfect candidates for applications involving liquid immersion due to their high quality (~10<sup>4</sup>) whispering gallery resonances evanescently excited in compact (4-15 &#x03BC;m) spherical resonators.
We observed whispering gallery resonances (WGMs) in semiconductor micropillars by employing geometry in which both excitation and collection of emission is in a direction normal to the sidewall surface of the pillars. The spectral positions of the peaks are found to be in a good agreement with the results of numerical modeling performed by finite difference(More)