Intrinsic Decoherence Mechanisms in the Microcavity Polariton Condensate

Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom.
Physical Review Letters (Impact Factor: 7.51). 09/2008; 101(6):067404. DOI: 10.1103/PhysRevLett.101.067404
Source: PubMed


The fundamental mechanisms which control the phase coherence of the polariton Bose-Einstein condensate (BEC) are determined. It is shown that the combination of number fluctuations and interactions leads to decoherence with a characteristic Gaussian decay of the first-order correlation function. This line shape, and the long decay times ( approximately 150 ps) of both first- and second-order correlation functions, are explained quantitatively by a quantum-optical model which takes into account interactions, fluctuations, and gain and loss in the system. Interaction limited coherence times of this type have been predicted for atomic BECs, but are yet to be observed experimentally.

Download full-text


Available from: D. Sanvitto, Oct 06, 2015
13 Reads
  • Source
    • "In a translationally invariant two-dimensional system, without a trap, superfluidity occurs via a Kosterlitz–Thouless superfluid (KTS) transition. Experiments on untrapped systems (Deng et al. 2002, 2003, 2006; Kasprzak et al. 2006; Baumberg et al. 2008; Love et al. 2008) have shown promising indications of the onset of spontaneous coherence effects. In principle, superfluidity in a finite two-dimensional system can be viewed as a type of BEC, with coherence length of the order of the size of the cloud of particles, what is sometimes called a 'quasicondensate' (Malpeuch et al. 2003). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The theory for spontaneous coherence of short-lived quasiparticles in two-dimensional excitonic systems is reviewed, in particular, quantum wells (QWs) and graphene layers (GLs) embedded in microcavities. Experiments with polaritons in an optical microcavity have already shown evidence of Bose-Einstein condensation (BEC) in the lowest quantum state in a harmonic trap. The theory of BEC and superfluidity of the microcavity excitonic polaritons in a harmonic potential trap is presented. Along the way, we determine a general method for defining the superfluid fraction in a two-dimensional trap, within the angular momentum representation. We discuss BEC of magnetoexcitonic polaritons (magnetopolaritons) in a QW and GL embedded in an optical microcavity in high magnetic field. It is shown that Rabi splitting in graphene is tunable by the external magnetic field B, while in a QW the Rabi splitting does not depend on the magnetic field in the strong B limit.
    Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences 12/2010; 368(1932):5459-82. DOI:10.1098/rsta.2010.0208 · 2.15 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The current status of research on exciton polaritons in semiconductor heterostructures with microcavities and the collective properties of polaritons under the conditions of Bose condensation are discussed.
    Semiconductors 07/2012; 46(7). DOI:10.1134/S1063782612070196 · 0.74 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An experiment is proposed, on the coherent quantum dynamics of a semiconductor microcavity containing quantum dots. Modeling the experiment using a generalized Dicke model, we show that a tailored excitation pulse can create an energy-dependent population of excitons, which subsequently evolves to a quantum condensate of excitons and photons. The population is created by a generalization of adiabatic rapid passage, and then condenses due to a dynamical analog of the BCS instability.
    Physical review. B, Condensed matter 09/2007; 79(16). DOI:10.1103/PhysRevB.79.165303 · 3.66 Impact Factor
Show more