Search Results

Now showing 1 - 4 of 4
  • Item
    Experimental observation of Berry phases in optical Möbius-strip microcavities
    (London [u.a.] : Nature Publ. Group, 2022) Wang, Jiawei; Valligatla, Sreeramulu; Yin, Yin; Schwarz, Lukas; Medina-Sánchez, Mariana; Baunack, Stefan; Lee, Ching Hua; Thomale, Ronny; Li, Shilong; Fomin, Vladimir M.; Ma, Libo; Schmidt, Oliver G.
    The Möbius strip, a fascinating loop structure with one-sided topology, provides a rich playground for manipulating the non-trivial topological behaviour of spinning particles, such as electrons, polaritons and photons, in both real and parameter spaces. For photons resonating in a Möbius-strip cavity, the occurrence of an extra phase—known as the Berry phase—with purely topological origin is expected due to its non-trivial evolution in parameter space. However, despite numerous theoretical investigations, characterizing the optical Berry phase in a Möbius-strip cavity has remained elusive. Here we report the experimental observation of the Berry phase generated in optical Möbius-strip microcavities. In contrast to theoretical predictions in optical, electronic and magnetic Möbius-topology systems where only Berry phase π occurs, we demonstrate that a variable Berry phase smaller than π can be acquired by generating elliptical polarization of resonating light. Möbius-strip microcavities as integrable and Berry-phase-programmable optical systems are of great interest in topological physics and emerging classical or quantum photonic applications.
  • Item
    Wavefunction of polariton condensates in a tunable acoustic lattice
    (Bristol : IOP, 2012) Cerda-Méndez, E.A.; Krizhanovskii, D.N.; Biermann, K.; Hey, R.; Skolnick, M.S.; Santos, P.V.
    We study the spatial coherence of polariton condensates subjected to coherent modulation by a one-dimensional tunable acoustic potential.We use an interferometric technique to measure the amplitude and phase of the macroscopic condensate wavefunction. By increasing the acoustic modulation amplitude, we track the transition from the extended wavefunction of the unperturbed condensate to a regime where the wavefunction is spatially modulated and then to a fully confined regime, where independent condensates form at the minima of the potential with negligible particle tunneling between adjacent sites.
  • Item
    Multi-stability and polariton formation in microcavity polaritonic waveguides
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2015) Slavcheva, Gabriela; Gorbach, Andrey V.; Pimenov, Alexander; Vladimirov, Andrei G.; Skryabin, Dmitry
    Nonlinear polaritons in microcavity waveguides are demonstrated to exhibit multi-stable behaviour and rich dynamics, including filamentation and soliton formation. We find that the multi-stability originates from co-existense of different transverse modes of the polaritonic waveguide. Modulational stability and conditions for multi-mode polariton solitons are studied. Soliton propagation in tilted, relative to the pump momentum, waveguides is demonstrated and a critical tilt angle for the soliton propagation is found.
  • Item
    The impact of microcavity wire width on polariton soliton existence and multistability
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2017) Slavcheva, Gabriela; Koleva, Mirella V.; Pimenov, Alexander
    We have developed a model of the nonlinear polariton dynamics in realistic 3D non-planar microcavity wires in the driven-dissipative regime [15]. We find that the typical microcavity optical bistability evolves into multi-stability upon variation of the model parameters. The origin of the multi-stability is discussed in detail. We apply linear perturbation analysis to modulational instabilities, and identify conditions for localisation of composite multi-mode polariton solitons in the triggered parametric oscillator regime. Further, we demonstrate stable polariton soliton propagation in tilted and tapered waveguides, and determine maximum tilt angles for which solitons are still found. Additionally, we study soliton amplitude and velocity dependence on the wire width, with a view towards device applications.