We report the observation of strong coupling between quantum well excitons and a guided mode of a semiconductor planar waveguide by observation of anticrossing in the dispersion. Strong spatial confinement of the optical mode allows a splitting between the two polariton modes of 5–6 meV for a single quantum well. Polaritons on resonance are shown to propagate with a characteristic decay length of 280 μm and a group velocity of 26 μm ps−1. This is a promising first step towards developing an alternative to microcavities for the study of rapidly propagating polaritons, which is particularly well suited to prospective on-chip polaritonic circuit applications.

A key property of equilibrium exciton-polariton condensates in semiconductor microcavities is the suppression of the Zeeman splitting under a magnetic field. By studying magnetophotoluminescence spectra from a GaAs microcavity, we show experimentally that a similar effect occurs in a nonequilibrium polariton condensate arising from polariton parametric scattering. In this case, the quenching of Zeeman splitting is related to a phase synchronization of spin-up and spin-down polarized polariton condensates caused by a nonlinear coupling via the coherent pump state.

We investigate the spontaneous formation of quantized vortices in microcavity polariton high density phases. Condensates formed in the optical parametric oscillator excitation scheme reveal single vortices in the case of a ring-shaped optical potential or in the presence of natural photonic disorder. We further investigate the dynamics of vortex formation for resonantly injected polaritons and observe the formation of vortex-antivortex pairs, but no single vortices. The observed effects are explained by the interplay between breaking of y → −y reflection symmetry in the system and conservation of optical angular momentum.

We study super-resolution capability of liquid-immersed high refractive index (n~1.9-2.1) barium titanate glass microspheres with diameters from several microns up to hundreds of microns. Imaging is provided in a conventional upright microscope with the spheres placed in a contact position with various semiconductor and metallic nanostructures. Using a commercial Blu-ray disk, we demonstrate an ability to discern 100 nm feature sizes which cannot be resolved by conventional microscopy. Using silver nanowires with diameter about 100 nm, we demonstrate ~1.7 times improvement in spatial resolution compared to conventional diffraction-limited far field microscopy. Using two-dimensional nanoplasmonic arrays, we demonstrate high resolution imaging by using objectives with surprisingly small numerical apertures. The last property is attractive for high-resolution imaging at long working distances. This imaging technique can be used in biomedical microscopy, microfluidics, and nanophotonics applications.

The presence of dislocations arising from strain relaxation strongly affects polaritons through their photonic component and ultimately limits experiments involving polariton propagation. In this work, we investigate the range of growth parameters to achieve high optical quality GaAs/AlxGa1−xAs-based microcavities containing strained InxGa1−xAs quantum wells and using differential interference contrast (Nomarski) microscopy deduce a design rule for homogeneous versus disordered structures. We illustrate the effect of disorder by contrasting observations of polariton condensates in relaxed and unrelaxed microcavities. In our optimized device, we generate a polariton condensate and deduce a lifetime for the interacting polariton fluid of 39 ± 2 ps.