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Related papers: Spontaneous Coherence in a Cold Exciton Gas

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The development of a Turing instability to a spatially modulated state in a photoexcited electron-hole system is proposed as a novel signature of exciton Bose statistics. We show that such an instability, which is driven by kinetics of…

Mesoscale and Nanoscale Physics · Physics 2008-04-12 L. S. Levitov , B. D. Simons , L. V. Butov

Motivated by the experiment of electrostatic conveyor belt for indirect excitons [A. G. Winbow, \textit{et al.}, Phys. Rev. Lett. \textbf{106}, 196806 (2011)], we study the exciton patterns for understanding the exciton dynamics. By…

Quantum Gases · Physics 2024-06-19 T. T. Zhao , Rui Li , C. S. Liu

A cavity-polariton, formed due to the strong coupling between exciton and cavity mode, is one of the most promising composite bosons for realizing macroscopic spontaneous coherence at high temperature. Up to date, most of polariton quantum…

Mesoscale and Nanoscale Physics · Physics 2010-07-28 Liaoxin Sun , Shulin Sun , Hongxing Dong , Wei Xie , M. Richard , Lei Zhou , L. S. Dang , Xuechu Shen , Zhanghai Chen

Indirect excitons -- pairs of electrons and holes spatially separated in semiconductor bilayers or quantum wells -- are known to undergo Bose-Einstein condensation and to form a quantum fluid. Here we show that this superfluid may…

Quantum Gases · Physics 2015-03-17 J. Boening , A. Filinov , M. Bonitz

The theory of what happens to a superfluid in a random field, known as the ``dirty boson'' problem, directly relates to a real experimental system presently under study by several groups, namely excitons in coupled semiconductor quantum…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Oleg L. Berman , Yurii E. Lozovik , David W. Snoke , Rob D. Coalson

We report on small-cluster exact-diagonalization calculations which prove the formation of electron-hole pairs (excitons) as prerequisite for spontaneous interlayer phase coherence in bilayer systems described by the extended…

Strongly Correlated Electrons · Physics 2013-07-25 T. Kaneko , S. Ejima , H. Fehske , Y. Ohta

We develop an approach based on stochastic quantum trajectories for an incoherently pumped system of interacting bosons relaxing their energy in a thermal reservoir. Our approach enables the study of the versatile coherence properties of…

Quantum Gases · Physics 2015-09-17 H. Flayac , I. G. Savenko , M. Möttönen , T. Ala-Nissila

The demonstration of Bose-Einstein condensation in atomic gases at micro-Kelvin temperatures is a striking landmark while its evidence for semiconductor excitons still is a long-awaited milestone. This situation was not foreseen because…

We report an experimental study of the spontaneous spatial and temporal coherence of polariton condensates generated in the optical parametric oscillator configuration, below and at the parametric threshold, and as a function of condensate…

Mesoscale and Nanoscale Physics · Physics 2011-11-22 R. Spano , J. Cuadra , C. Lingg , D. Sanvitto , M. D. Martin , P. R. Eastham , M. van der Poel , J. M. Hvam , L. Vina

Exciton condensation--an interaction-driven, macroscopically coherent paired-fermion state--offers the prospect for dissipationless energy transport in solids, akin to that in superconductivity. Although their light effective mass and…

Excitons are the neutral quasiparticles that form when Coulomb interactions create bound states between electrons and holes. Due to their bosonic nature, excitons are expected to condense and exhibit superfluidity at sufficiently low…

Mesoscale and Nanoscale Physics · Physics 2024-09-04 Hong-Yi Xie , Pouyan Ghaemi , Matteo Mitrano , Bruno Uchoa

We show that a quasi-two dimensional condensate of optically active excitons emits coherent light even in the absence of population inversion. This allows an unambiguous and clear experimental detection of the condensed phase. We prove…

Condensed Matter · Physics 2015-06-25 J. Fernandez-Rossier , C. Tejedor , R. Merlin

The dynamics of the expansion of the first order spatial coherence g(1) for a polariton system in a high-Q GaAs microcavity was investigated on the basis of Young's double slit experiment under 3 ps pulse excitation at the conditions of…

Mesoscale and Nanoscale Physics · Physics 2013-04-18 V. V. Belykh , N. N. Sibeldin , V. D. Kulakovskii , M. M. Glazov , M. A. Semina , C. Schneider , S. Höfling , M. Kamp , A. Forchel

A quasi-exciton condensate is a phase characterized by quasi-long range order of an exciton (electron-hole pair) order parameter. Such a phase can arise naturally in a system of two parallel oppositely doped quantum wires, coupled by…

Mesoscale and Nanoscale Physics · Physics 2015-06-17 Yochai Werman , Erez Berg

We have succeeded in trapping indirect excitons in coupled quantum wells in a harmonic potential minimum via inhomogeneous applied stress and electric field. These excitons exhibit a strong Stark shift (over 60 meV), long lifetime (100 ns),…

Strongly Correlated Electrons · Physics 2007-05-23 V. Negoita , D. W. Snoke , K. Eberl

Recently a new type of system exhibiting spontaneous coherence has emerged -- the exciton-polariton condensate. Exciton-polaritons (or polaritons for short) are bosonic quasiparticles that exist inside semiconductor microcavities,…

Quantum Gases · Physics 2015-06-23 Tim Byrnes , Na Young Kim , Yoshihisa Yamamoto

We evaluate the effect of diffraction-limited resolution of the optical system on the estimates of the coherence length of 2D excitons deduced from the interferometric study of the exciton emission. The results are applied for refining our…

Mesoscale and Nanoscale Physics · Physics 2008-07-08 M. M. Fogler , Sen Yang , A. T. Hammack , L. V. Butov , A. C. Gossard

Dark excitons are of fundamental importance in a broad range of contexts, but are difficult to study using conventional optical spectroscopy due to their weak interaction with light. We show how coherent multidimensional spectroscopy can…

Optics · Physics 2016-08-31 Jonathan O. Tollerud , Steven T. Cundiff , Jeffrey A. Davis

Coherence properties are central to quantum systems and are at the heart of phenomena such as superconductivity. Here we study coherence properties of an ultracold Bose gas in a two-dimensional optical lattice across the thermal phase…

Quantum Gases · Physics 2024-10-15 Justus C. Brüggenjürgen , Mathis S. Fischer , Christof Weitenberg

Macroscopic quantum coherence emerges when bosons condense into a Bose-Einstein condensate (BEC). First observed as a single-component superfluid in helium, BECs later emerged in ultracold atomic gases at nanokelvin temperatures as weakly…