Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1009.3505 · Physical Review B

Bloch oscillations of an exciton-polariton Bose-Einstein condensate

Hugo Flayac, Dmitry D. Solnyshkov, G. Malpuech

Published Jan 21, 2011• 25 citations
arXivHTMLPDF

Abstract

We study theoretically Bloch oscillations of half-matter, half-light quasiparticles: exciton-polaritons. We propose an original structure for the observation of this phenomenon despite the constraints imposed by the relatively short lifetime of the particles and the limitations on the engineered periodic potential. First, we focus on the linear regime in a perfect lattice where regular oscillations are obtained. Second, we take into account a realistic structural disorder known to localize noninteracting particles, which is quite dramatic for propagation-related phenomena. In the nonlinear condensed regime the renormalization of the energy provided by interactions between particles allows us to screen efficiently the disorder and to recover oscillations. This effect is useful only in a precise range of parameters outside of which the system becomes dynamically unstable. For a large chemical potential of the order of the potential's amplitude, a strong Landau-Zener tunneling tends to completely delocalize particles.

DOI
10.1103/physrevb.83.045412

Related papers

Dynamics of Bloch oscillations in disordered lattice potentials

T. Schulte, S. Drenkelforth, G. Kleine Büning +4 more

We present a detailed analysis of the dynamics of Bloch oscillations of Bose-Einstein condensates in disordered lattice potentials. Due to the disorder and the interparticle interactions these oscillations undergo a dephasing, reflected in a damping of the center of mass oscillations, which should be observable under realistic experimental conditions. The interplay between interactions and disorder is far from trivial, ranging from an interaction-enhanced damping due to modulational instability for strong interactions, to an interaction-reduced damping due to a dynamical screening of the disorder potential.

arXiv:0707.3131•Physical Review A•Feb 6, 2008•34 citations

Nonlinearity-induced effects of Bose-Einstein condensates in periodic potentials

O. Morsch

In BECs, collisions between condensate atoms give rise to a nonlinear contribution to the dynamics which is typically included as a mean-field term in the Schrodinger equation. This nonlinearity leads to a modification of well-known effects associated with matter waves in periodic potentials and adds a number of phenomena that are absent in the linear problem. We focused on the dynamics of a BEC in an accelerated optical lattice. In the linear case, this gives rise to Bloch oscillations and, above a critical acceleration, to Landau-Zener tunneling. In the nonlinear case, the probability for Landau-Zener tunneling is modified depending on the direction in which it occurs between two bands. By varying the acceleration of the optical lattice and measuring the time-dependence of the interference contrast, we were able to identify the instability regime and the characteristic time in which the dynamical instability destroys the interference pattern. Furthermore, we observed an increase in the condensate dimensions perpendicular to the lattice direction when the unstable region was reached. This indicates a mechanism whereby the longitudinal instability leads to an increase in the transverse release energy

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jan 25, 2006•0 citations

Exciton-Polariton Bose-Einstein Condensates

B. Deveaud

Exciton-polaritons, mixed light-matter quasiparticles in semiconductors, have recently shown evidence for Bose-Einstein condensation. Some of the properties of condensates of exciton-polaritons are reviewed in this article. We first discuss the spontaneous appearance of long-range order and the way this can be easily accessed in the case of polariton fluids. We show that the Penrose-Onsager criterion is valid even for such a very special case of condensate. We then describe the experiments that allow observation of topological defects in the fluid: quantized vortices, half vortices, and hyperbolic spin vortices. We demonstrate through the comparison with the gross Pitaevskii equation that the appearance and stability of such vortices are linked with the dissipative nature of the condensate together with the presence of disorder. We then briefly summarize the experiments on superfluid behavior of the polaritons at large-enough densities and expand somewhat more on the dynamical behavior of turbulence in the wake of an obstacle, with the appearance of vortex streets. We finally show that the Bogoliubov transformation has been revealed through four-wave mixing experiments.

Annual Review of Condensed Matter Physics•Mar 1, 2015•29 citations

Bose-Einstein condensates in 1D optical lattices: nonlinearity and Wannier-Stark spectra

E. Arimondo, D. Ciampini, O. Morsch

We present our experimental investigations on the subject of nonlinearity-modified Bloch-oscillations and of nonlinear Landau-Zener tunneling between two energy bands in a rubidium Bose Einstein condensate in an accelerated periodic potential. Nonlinearity introduces an asymmetry in Landau-Zener tunneling. We also present measurements of resonantly enhanced tunneling between the Wannier-Stark energy levels for Bose-Einstein condensates loaded into an optical lattice.

arXiv:0708.0479•Aug 3, 2007•0 citations

Bloch Oscillations and Mean-Field Effects of Bose-Einstein Condensates in 1D Optical Lattices

O. Morsch, Jörg Helge Müller, Matteo Cristiani +2 more

We have loaded Bose-Einstein condensates into one-dimensional, off-resonant optical lattices and accelerated them by chirping the frequency difference between the two lattice beams. For small values of the lattice well depth, Bloch oscillations were observed. Reducing the potential depth further, Landau-Zener tunneling out of the lowest lattice band, leading to a breakdown of the oscillations, was also studied and used as a probe for the effective potential resulting from mean-field interactions as predicted by Choi and Niu [Phys. Rev. Lett. 82, 2022 (1999)]. The effective potential was measured for various condensate densities and trap geometries, yielding good qualitative agreement with theoretical calculations.

arXiv:cond-mat/0108457•Physical Review Letters•Sep 13, 2001•548 citations

Superfluidity of Bose–Einstein condensate in an optical lattice: Landau–Zener tunnelling and dynamical instability

Biao Wu, Qian Niu

Superflow of a Bose–Einstein condensate in an optical lattice is represented by a Bloch wave, a plane wave with periodic modulation of the amplitude. We review the theoretical results of the interaction effects in the energy dispersion of the Bloch waves and in the linear stability of such waves. For sufficiently strong repulsion between the atoms, the lowest Bloch band develops a loop at the edge of the Brillouin zone, with the dramatic consequence of a finite probability of Landau–Zener tunnelling even in the limit of a vanishing external force. Superfluidity can exist in the central region of the Brillouin zone in the presence of a repulsive interaction, beyond which Landau instability takes place where the system can lower its energy by making a transition into states with smaller Bloch wavenumbers. In the outer part of the region of Landau instability, the Bloch waves are also dynamically unstable in the sense that a small initial deviation grows exponentially in time. In the inner region of Landau instability, a Bloch wave is dynamically stable in the absence of persistent external perturbations. Experimental implications of our findings will be discussed.

arXiv:cond-mat/0306411•New Journal of Physics•Jul 31, 2003•288 citations
We study theoretically Bloch oscillations of half-matter, half-light quasiparticles: exciton-polaritons. We propose an original structure for the observation of this phenomenon despite the constraints imposed by the relatively short lifetime of the particles and the limitations on the engineered periodic potential. First, we focus on the linear regime in a perfect lattice where regular oscillations are obtained. Second, we take into account a realistic structural disorder known to localize noninteracting particles, which is quite dramatic for propagation-related phenomena. In the nonlinear condensed regime the renormalization of the energy provided by interactions between particles allows us to screen efficiently the disorder and to recover oscillations. This effect is useful only in a precise range of parameters outside of which the system becomes dynamically unstable. For a large chemical potential of the order of the potential's amplitude, a strong Landau-Zener tunneling tends to completely delocalize particles.
We present a detailed analysis of the dynamics of Bloch oscillations of Bose-Einstein condensates in disordered lattice potentials. Due to the disorder and the interparticle interactions these oscillations undergo a dephasing, reflected in a damping of the center of mass oscillations, which should be observable under realistic experimental conditions. The interplay between interactions and disorder is far from trivial, ranging from an interaction-enhanced damping due to modulational instability for strong interactions, to an interaction-reduced damping due to a dynamical screening of the disorder potential.
In BECs, collisions between condensate atoms give rise to a nonlinear contribution to the dynamics which is typically included as a mean-field term in the Schrodinger equation. This nonlinearity leads to a modification of well-known effects associated with matter waves in periodic potentials and adds a number of phenomena that are absent in the linear problem. We focused on the dynamics of a BEC in an accelerated optical lattice. In the linear case, this gives rise to Bloch oscillations and, above a critical acceleration, to Landau-Zener tunneling. In the nonlinear case, the probability for Landau-Zener tunneling is modified depending on the direction in which it occurs between two bands. By varying the acceleration of the optical lattice and measuring the time-dependence of the interference contrast, we were able to identify the instability regime and the characteristic time in which the dynamical instability destroys the interference pattern. Furthermore, we observed an increase in the condensate dimensions perpendicular to the lattice direction when the unstable region was reached. This indicates a mechanism whereby the longitudinal instability leads to an increase in the transverse release energy
Exciton-polaritons, mixed light-matter quasiparticles in semiconductors, have recently shown evidence for Bose-Einstein condensation. Some of the properties of condensates of exciton-polaritons are reviewed in this article. We first discuss the spontaneous appearance of long-range order and the way this can be easily accessed in the case of polariton fluids. We show that the Penrose-Onsager criterion is valid even for such a very special case of condensate. We then describe the experiments that allow observation of topological defects in the fluid: quantized vortices, half vortices, and hyperbolic spin vortices. We demonstrate through the comparison with the gross Pitaevskii equation that the appearance and stability of such vortices are linked with the dissipative nature of the condensate together with the presence of disorder. We then briefly summarize the experiments on superfluid behavior of the polaritons at large-enough densities and expand somewhat more on the dynamical behavior of turbulence in the wake of an obstacle, with the appearance of vortex streets. We finally show that the Bogoliubov transformation has been revealed through four-wave mixing experiments.
We have loaded Bose-Einstein condensates into one-dimensional, off-resonant optical lattices and accelerated them by chirping the frequency difference between the two lattice beams. For small values of the lattice well depth, Bloch oscillations were observed. Reducing the potential depth further, Landau-Zener tunneling out of the lowest lattice band, leading to a breakdown of the oscillations, was also studied and used as a probe for the effective potential resulting from mean-field interactions as predicted by Choi and Niu [Phys. Rev. Lett. 82, 2022 (1999)]. The effective potential was measured for various condensate densities and trap geometries, yielding good qualitative agreement with theoretical calculations.
Superflow of a Bose–Einstein condensate in an optical lattice is represented by a Bloch wave, a plane wave with periodic modulation of the amplitude. We review the theoretical results of the interaction effects in the energy dispersion of the Bloch waves and in the linear stability of such waves. For sufficiently strong repulsion between the atoms, the lowest Bloch band develops a loop at the edge of the Brillouin zone, with the dramatic consequence of a finite probability of Landau–Zener tunnelling even in the limit of a vanishing external force. Superfluidity can exist in the central region of the Brillouin zone in the presence of a repulsive interaction, beyond which Landau instability takes place where the system can lower its energy by making a transition into states with smaller Bloch wavenumbers. In the outer part of the region of Landau instability, the Bloch waves are also dynamically unstable in the sense that a small initial deviation grows exponentially in time. In the inner region of Landau instability, a Bloch wave is dynamically stable in the absence of persistent external perturbations. Experimental implications of our findings will be discussed.