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Tian C, Zhou B, Xu C, Zhang Y, Zheng X, Zhang J, Zhang L, Dong H, Zhou W. Polariton-Polariton Interactions Revealed in a One-dimensional Whispering Gallery Microcavity. NANO LETTERS 2020; 20:1552-1560. [PMID: 32097561 DOI: 10.1021/acs.nanolett.9b04121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Coulomb interactions are essential to the dynamics and optical properties of exciton-polaritons. Here, we report an experimental observation of polariton-polariton interactions far beyond theory in a one-dimensional whispering gallery microcavity. Based on the unique half-light half-matter nature, we were able to clarify the effects of excitons, quantum confinement, and nonthermalized polariton distribution in the measurements of the polaritonic interactions. Spectacularly, our position-scan and power-scan investigations both revealed that the polariton-polariton interaction strength is up to 2 orders of magnitude larger than theoretical predictions. These results suggest that polaritonic interactions are far more complicated than the expectation and should be re-examined in polariton physics and devices involving polaritonic interactions.
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Affiliation(s)
- Chuan Tian
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Beier Zhou
- Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai, China
| | - Chunyan Xu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yingjun Zhang
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiamei Zheng
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jian Zhang
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Long Zhang
- Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai, China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No.1, Sub-Lane Xiangshan, Xihu District, 310024 Hangzhou, China
| | - Hongxing Dong
- Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai, China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No.1, Sub-Lane Xiangshan, Xihu District, 310024 Hangzhou, China
| | - Weihang Zhou
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
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Lee KH, Lee C, Min H, Chung SB. Phase Transitions of the Polariton Condensate in 2D Dirac Materials. PHYSICAL REVIEW LETTERS 2018; 120:157601. [PMID: 29756851 DOI: 10.1103/physrevlett.120.157601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Indexed: 06/08/2023]
Abstract
For the quantum well in an optical microcavity, the interplay of the Coulomb interaction and the electron-photon (e-ph) coupling can lead to the hybridizations of the exciton and the cavity photon known as polaritons, which can form the Bose-Einstein condensate above a threshold density. Additional physics due to the nontrivial Berry phase comes into play when the quantum well consists of the gapped two-dimensional Dirac material such as the transition metal dichalcogenide MoS_{2} or WSe_{2}. Specifically, in forming the polariton, the e-ph coupling from the optical selection rule due to the Berry phase can compete against the Coulomb electron-electron (e-e) interaction. We find that this competition gives rise to a rich phase diagram for the polariton condensate involving both topological and symmetry breaking phase transitions, with the former giving rise to the quantum anomalous Hall and the quantum spin Hall phases.
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Affiliation(s)
- Ki Hoon Lee
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul National University, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Changhee Lee
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Hongki Min
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - Suk Bum Chung
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul National University, Seoul 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
- Department of Physics, University of Seoul, Seoul 02504, Korea
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Daskalakis KS, Maier SA, Kéna-Cohen S. Spatial Coherence and Stability in a Disordered Organic Polariton Condensate. PHYSICAL REVIEW LETTERS 2015; 115:035301. [PMID: 26230799 DOI: 10.1103/physrevlett.115.035301] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Indexed: 06/04/2023]
Abstract
Although only a handful of organic materials have shown polariton condensation, their study is rapidly becoming more accessible. The spontaneous appearance of long-range spatial coherence is often recognized as a defining feature of such condensates. In this Letter, we study the emergence of spatial coherence in an organic microcavity and demonstrate a number of unique features stemming from the peculiarities of this material set. Despite its disordered nature, we find that correlations extend over the entire spot size, and we measure g(1)(r,r') values of nearly unity at short distances and of 50% for points separated by nearly 10 μm . We show that for large spots, strong shot-to-shot fluctuations emerge as varying phase gradients and defects, including the spontaneous formation of vortices. These are consistent with the presence of modulation instabilities. Furthermore, we find that measurements with flat-top spots are significantly influenced by disorder and can, in some cases, lead to the formation of mutually incoherent localized condensates.
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Affiliation(s)
- K S Daskalakis
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | - S A Maier
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | - S Kéna-Cohen
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, Québec H3C 3A7, Canada
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Bittner ER, Zaster S, Silva C. Thermodynamics of exciton/polaritons in one and two dimensional organic single-crystal microcavities. Phys Chem Chem Phys 2012; 14:3226-33. [PMID: 22416284 DOI: 10.1039/c2cp23204a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We consider here the thermodynamics and phase-diagram of exciton/polaritons formed in low-dimensional organic single-crystal microcavities. Using the Dicke model for a lattice of Frenkel excitons coupled to a common cavity mode, we explore the transition between normal and condensate regimes as depending upon the exciton band-width and temperature of the polariton gas. We show that for one-dimensional conjugated polymers, the coexistence curve at low temperatures shifts towards lower critical coupling strengths as the exciton band-width is increased. We also consider the effect of orientational disorder in a two-dimensional polyacene slab on the formation of the polariton BEC. Our results indicate that while a small degree of orientational disorder will not have a profound effect on the critical exciton/photon coupling strength needed to produce the transition from normal to BEC regimes, BEC will likely be suppressed in glassy or strongly disordered molecular films.
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Affiliation(s)
- Eric R Bittner
- Department of Chemistry, University of Houston, Houston, TX 77204, USA.
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Bittner ER, Silva C. Estimating the conditions for polariton condensation in organic thin-film microcavities. J Chem Phys 2012; 136:034510. [PMID: 22280770 DOI: 10.1063/1.3678015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We examine the possibility of observing Bose condensation of a confined two-dimensional polariton gas in an organic quantum well. We deduce a suitable parameterization of a model polynomial Hamiltonian based upon the cavity geometry, the biexciton binding energy, and similar spectroscopic and structural data. By converting the sum-over-states to a semiclassical integration over D-dimensional phase space, we arrive at a principle of correspondence between ideal and non-ideal Bose gases that share a common critical exponent. Using our results, we can calculate the properties for a model cavity containing an anthracene thin film.
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Affiliation(s)
- Eric R Bittner
- Department of Chemistry, University of Houston, Houston, Texas 77204, USA.
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Eastham PR. The new physics of non-equilibrium condensates: insights from classical dynamics. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:295210. [PMID: 21483062 DOI: 10.1088/0953-8984/19/29/295210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We discuss the dynamics of classical Dicke-type models, aiming to clarify the mechanisms by which coherent states could develop in potentially non-equilibrium systems such as semiconductor microcavities. We present simulations of an undamped model which show spontaneous coherent states with persistent oscillations in the magnitude of the order parameter. These states are generalizations of superradiant ringing to the case of inhomogeneous broadening. They correspond to the persistent gap oscillations proposed in fermionic atomic condensates, and arise from a variety of initial conditions. We show that introducing randomness into the couplings can suppress the oscillations, leading to a limiting dynamics with a time-independent order parameter. This demonstrates that non-equilibrium generalizations of polariton condensates can be created even without dissipation. We explain the dynamical origins of the coherence in terms of instabilities of the normal state, and consider how it can additionally develop through scattering and dissipation.
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Affiliation(s)
- P R Eastham
- Theory of Condensed Matter, Cavendish Laboratory, Cambridge CB3 0HE, UK
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Keeling J. Coulomb interactions, gauge invariance, and phase transitions of the Dicke model. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:295213. [PMID: 21483065 DOI: 10.1088/0953-8984/19/29/295213] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Phase transitions of a generalized Dicke model in the Coulomb gauge-including A(2) terms in the matter-radiation coupling, as well as direct dipole-dipole interaction terms-are studied. After a brief review of previous work on the 'no-go theorem' for phase transitions in the Dicke model, it is shown that a consistent truncation of the radiation modes and of the direct interactions leads to a model that does have a phase transition. When transformed to the electric dipole gauge, such a system takes exactly the form of the original Dicke Hamiltonian, which displays the expected phase transition.
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Martín MD, Aichmayr G, Amo A, Ballarini D, Kłopotowski L, Viña L. Polariton and spin dynamics in semiconductor microcavities under non-resonant excitation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2007; 19:295204. [PMID: 21483056 DOI: 10.1088/0953-8984/19/29/295204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Semiconductor microcavities offer an ideal scenario to study strong radiation-matter interactions. In this paper we review the temporal dynamics of polaritons in II-VI and III-V based microcavities under non-resonant excitation conditions. We present evidence of final-state stimulated scattering and discuss the spin-dependent emission, which exhibits a remarkably rich behaviour.
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Affiliation(s)
- M D Martín
- SEMICUAM. Departamento de Física de Materiales, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
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Malpuech G, Solnyshkov DD, Ouerdane H, Glazov MM, Shelykh I. Bose glass and superfluid phases of cavity polaritons. PHYSICAL REVIEW LETTERS 2007; 98:206402. [PMID: 17677719 DOI: 10.1103/physrevlett.98.206402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Indexed: 05/16/2023]
Abstract
We report the calculation of cavity exciton-polariton phase diagram including realistic structural disorder. With increasing density polaritons first undergo a quasiphase transition toward a Bose glass: the condensate is localized in at least one minimum of the disorder potential. A further increase of the density leads to a percolation process of the polariton fluid giving rise to a Kosterlitz-Thouless phase transition toward superfluidity. The spatial representation of the condensate wave function as well as the spectrum of elementary excitations are obtained from the Gross-Pitaevskii equation for all the phases.
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Affiliation(s)
- G Malpuech
- LASMEA, CNRS-Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière Cedex France
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Kasprzak J, Richard M, Kundermann S, Baas A, Jeambrun P, Keeling JMJ, Marchetti FM, Szymańska MH, André R, Staehli JL, Savona V, Littlewood PB, Deveaud B, Dang LS. Bose–Einstein condensation of exciton polaritons. Nature 2006; 443:409-14. [PMID: 17006506 DOI: 10.1038/nature05131] [Citation(s) in RCA: 687] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Accepted: 07/24/2006] [Indexed: 11/08/2022]
Abstract
Phase transitions to quantum condensed phases--such as Bose-Einstein condensation (BEC), superfluidity, and superconductivity--have long fascinated scientists, as they bring pure quantum effects to a macroscopic scale. BEC has, for example, famously been demonstrated in dilute atom gas of rubidium atoms at temperatures below 200 nanokelvin. Much effort has been devoted to finding a solid-state system in which BEC can take place. Promising candidate systems are semiconductor microcavities, in which photons are confined and strongly coupled to electronic excitations, leading to the creation of exciton polaritons. These bosonic quasi-particles are 10(9) times lighter than rubidium atoms, thus theoretically permitting BEC to occur at standard cryogenic temperatures. Here we detail a comprehensive set of experiments giving compelling evidence for BEC of polaritons. Above a critical density, we observe massive occupation of the ground state developing from a polariton gas at thermal equilibrium at 19 K, an increase of temporal coherence, and the build-up of long-range spatial coherence and linear polarization, all of which indicate the spontaneous onset of a macroscopic quantum phase.
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Affiliation(s)
- J Kasprzak
- CEA-CNRS-UJF joint group Nanophysique et Semiconducteurs, Laboratoire de Spectrométrie Physique, UMR5588, Université J. Fourier-Grenoble, F-38402 Saint Martin d'Hères cedex, France.
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Szymańska MH, Keeling J, Littlewood PB. Nonequilibrium quantum condensation in an incoherently pumped dissipative system. PHYSICAL REVIEW LETTERS 2006; 96:230602. [PMID: 16803361 DOI: 10.1103/physrevlett.96.230602] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2006] [Indexed: 05/10/2023]
Abstract
We study spontaneous quantum coherence in an out of an equilibrium system, coupled to multiple baths describing pumping and decay. For a range of parameters describing coupling to, and occupation of the baths, a stable steady-state condensed solution exists. The presence of pumping and decay significantly modifies the spectra of phase fluctuations, leading to correlation functions that differ both from an isolated condensate and from a laser.
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Affiliation(s)
- M H Szymańska
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, United Kingdom
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