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Jia C, Liang Z. Interaction between an Impurity and Nonlinear Excitations in a Polariton Condensate. ENTROPY (BASEL, SWITZERLAND) 2022; 24:1789. [PMID: 36554194 PMCID: PMC9778002 DOI: 10.3390/e24121789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
Exploring the dynamics of a mobile impurity immersed in field excitations is challenging, as it requires to account for the entanglement between the impurity and the surrounding excitations. To this end, the impurity's effective mass has to be considered as finite, rather than infinite. Here, we theoretically investigate the interaction between a finite-mass impurity and a dissipative soliton representing nonlinear excitations in the polariton Bose-Einstein condensate (BEC). Using the Lagrange variational method and the open-dissipative Gross-Pitaevskii equation, we analytically derive the interaction phase diagram between the impurity and a dissipative bright soliton in the polariton BEC. Depending on the impurity mass, we find the dissipative soliton colliding with the impurity can transmit through, get trapped, or be reflected. This work opens a new perspective in understanding the impurity dynamics when immersed in field excitations, as well as potential applications in information processing with polariton solitons.
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Room-temperature polariton quantum fluids in halide perovskites. Nat Commun 2022; 13:7388. [DOI: 10.1038/s41467-022-34987-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/14/2022] [Indexed: 12/02/2022] Open
Abstract
AbstractQuantum fluids exhibit quantum mechanical effects at the macroscopic level, which contrast strongly with classical fluids. Gain-dissipative solid-state exciton-polaritons systems are promising emulation platforms for complex quantum fluid studies at elevated temperatures. Recently, halide perovskite polariton systems have emerged as materials with distinctive advantages over other room-temperature systems for future studies of topological physics, non-Abelian gauge fields, and spin-orbit interactions. However, the demonstration of nonlinear quantum hydrodynamics, such as superfluidity and Čerenkov flow, which is a consequence of the renormalized elementary excitation spectrum, remains elusive in halide perovskites. Here, using homogenous halide perovskites single crystals, we report, in both one- and two-dimensional cases, the complete set of quantum fluid phase transitions from normal classical fluids to scatterless polariton superfluids and supersonic fluids—all at room temperature, clear consequences of the Landau criterion. Specifically, the supersonic Čerenkov wave pattern was observed at room temperature. The experimental results are also in quantitative agreement with theoretical predictions from the dissipative Gross-Pitaevskii equation. Our results set the stage for exploring the rich non-equilibrium quantum fluid many-body physics at room temperature and also pave the way for important polaritonic device applications.
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Jheng SD, Chen TW, Cheng SC. Spontaneous giant vortices and circular supercurrents in a trapped exciton-polariton condensate. OPTICS EXPRESS 2022; 30:35325-35337. [PMID: 36258486 DOI: 10.1364/oe.468330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/23/2022] [Indexed: 06/16/2023]
Abstract
We theoretically study an exciton-polariton condensate trapped in a harmonic potential with an annular pump. With a circular pump, predictions were made for a spontaneous rotating vortex lattice packed by singly quantized vortices. If the circular pump is replaced by an annular pump, singly quantized vortices are absorbed into the central hole and form a multiply quantized vortex. For a sufficiently narrow annular width, all vortices are absorbed into the central hole, ultimately forming a giant vortex with supersonic circular supercurrents flowing around it. Vortex-antivortex pairs can be generated if a defect is present in these supersonic circular supercurrents. We further discover that the motion of the vortex-antivortex pairs depends on the position at which they were generated. We suggest that this property can be used to control whether the velocity of the circular supercurrents is above or below the sound velocity.
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Tian Z, Wu L, Zhang L, Jing J, Du J. Probing Lorentz-invariance-violation-induced nonthermal Unruh effect in quasi-two-dimensional dipolar condensates. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.106.l061701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
Recent studies have demonstrated that higher than two-body bath-impurity correlations are not important for quantitatively describing the ground state of the Bose polaron. Motivated by the above, we employ the so-called Gross Ansatz (GA) approach to unravel the stationary and dynamical properties of the homogeneous one-dimensional Bose-polaron for different impurity momenta and bath-impurity couplings. We explicate that the character of the equilibrium state crossovers from the quasi-particle Bose polaron regime to the collective-excitation stationary dark-bright soliton for varying impurity momentum and interactions. Following an interspecies interaction quench the temporal orthogonality catastrophe is identified, provided that bath-impurity interactions are sufficiently stronger than the intraspecies bath ones, thus generalizing the results of the confined case. This catastrophe originates from the formation of dispersive shock wave structures associated with the zero-range character of the bath-impurity potential. For initially moving impurities, a momentum transfer process from the impurity to the dispersive shock waves via the exerted drag force is demonstrated, resulting in a final polaronic state with reduced velocity. Our results clearly demonstrate the crucial role of non-linear excitations for determining the behavior of the one-dimensional Bose polaron.
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Seetharam K, Shchadilova Y, Grusdt F, Zvonarev MB, Demler E. Dynamical Quantum Cherenkov Transition of Fast Impurities in Quantum Liquids. PHYSICAL REVIEW LETTERS 2021; 127:185302. [PMID: 34767413 DOI: 10.1103/physrevlett.127.185302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
The challenge of understanding the dynamics of a mobile impurity in an interacting quantum many-body medium comes from the necessity of including entanglement between the impurity and excited states of the environment in a wide range of energy scales. In this Letter, we investigate the motion of a finite mass impurity injected into a three-dimensional quantum Bose fluid as it starts shedding Bogoliubov excitations. We uncover a transition in the dynamics as the impurity's velocity crosses a critical value that depends on the strength of the interaction between the impurity and bosons as well as the impurity's recoil energy. We find that in injection experiments, the two regimes differ not only in the character of the impurity velocity abatement but also exhibit qualitative differences in the Loschmidt echo, density ripples excited in the Bose-Einstein condensate, and momentum distribution of scattered bosonic particles. The transition is a manifestation of a dynamical quantum Cherenkov effect and should be experimentally observable with ultracold atoms using Ramsey interferometry, rf spectroscopy, absorption imaging, and time-of-flight imaging.
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Affiliation(s)
- Kushal Seetharam
- Department of Electrical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Yulia Shchadilova
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Fabian Grusdt
- Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universität München, Theresienstrasse 37, München D-80333, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, D-80799 München, Germany
| | - Mikhail B Zvonarev
- Université Paris-Saclay, CNRS, LPTMS, 91405 Orsay, France
- Russian Quantum Center, Skolkovo, Moscow 143025, Russia
- St. Petersburg Department of V.A. Steklov Mathematical Institute of Russian Academy of Sciences, Fontanka 27, St. Petersburg 191023, Russia
| | - Eugene Demler
- Institute for Theoretical Physics, ETH Zürich, 8093 Zürich, Switzerland
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Karnieli A, Rivera N, Arie A, Kaminer I. Superradiance and Subradiance due to Quantum Interference of Entangled Free Electrons. PHYSICAL REVIEW LETTERS 2021; 127:060403. [PMID: 34420316 DOI: 10.1103/physrevlett.127.060403] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
When multiple quantum emitters radiate, their emission rate may be enhanced or suppressed due to collective interference in a process known as super- or subradiance. Such processes are well known to occur also in light emission from free electrons, known as coherent cathodoluminescence. Unlike atomic systems, free electrons have an unbounded energy spectrum, and, thus, all their emission mechanisms rely on electron recoil, in addition to the classical properties of the dielectric medium. To date, all experimental and theoretical studies of super- and subradiance from free electrons assumed only classical correlations between particles. However, dependence on quantum correlations, such as entanglement between free electrons, has not been studied. Recent advances in coherent shaping of free-electron wave functions motivate the investigation of such quantum regimes of super- and subradiance. In this Letter, we show how a pair of coincident path-entangled electrons can demonstrate either super- or subradiant light emission, depending on the two-particle wave function. By choosing different free-electron Bell states, the spectrum and emission pattern of the light can be reshaped, in a manner that cannot be accounted for by a classical mixed state. We show these results for light emission in any optical medium and discuss their generalization to many-body quantum states. Our findings suggest that light emission can be sensitive to the explicit quantum state of the emitting matter wave and possibly serve as a nondestructive measurement scheme for measuring the quantum state of many-body systems.
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Affiliation(s)
- Aviv Karnieli
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Nicholas Rivera
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Ady Arie
- School of Electrical Engineering, Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ido Kaminer
- Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
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Karnieli A, Rivera N, Arie A, Kaminer I. The coherence of light is fundamentally tied to the quantum coherence of the emitting particle. SCIENCE ADVANCES 2021; 7:eabf8096. [PMID: 33931454 PMCID: PMC8087421 DOI: 10.1126/sciadv.abf8096] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 03/19/2021] [Indexed: 05/20/2023]
Abstract
Coherent emission of light by free charged particles is believed to be successfully captured by classical electromagnetism in all experimental settings. However, recent advances triggered fundamental questions regarding the role of the particle wave function in these processes. Here, we find that even in seemingly classical experimental regimes, light emission is fundamentally tied to the quantum coherence and correlations of the emitting particle. We use quantum electrodynamics to show how the particle's momentum uncertainty determines the optical coherence of the emitted light. We find that the temporal duration of Cherenkov radiation, envisioned for almost a century as a shock wave of light, is limited by underlying entanglement between the particle and light. Our findings enable new capabilities in electron microscopy for measuring quantum correlations of shaped electrons. Last, we propose new Cherenkov detection schemes, whereby measuring spectral photon autocorrelations can unveil the wave function structure of any charged high-energy particle.
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Affiliation(s)
- Aviv Karnieli
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
| | - Nicholas Rivera
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ady Arie
- School of Electrical Engineering, Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ido Kaminer
- Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
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9
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Sakhel RR, Sakhel AR. Effect of trapping geometry on the parametric resonances in a disordered Bose-Einstein condensate driven by an oscillating potential. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:315401. [PMID: 32160602 DOI: 10.1088/1361-648x/ab7f06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/11/2020] [Indexed: 06/10/2023]
Abstract
We report parametric resonances (PRs) in a numerical investigation of a driven one-dimensional, interacting, and disordered Bose-Einstein condensate (BEC) confined in different traps. The BEC is excited by an oscillating Gaussian obstacle along a broad range of driving frequencies Ω. The PRs are detected via a quantity that is closely related to the time-average of the kinetic energy. The significant result of this work is that the trapping geometry plays a major role in defining the values of Ω at which PRs arise and controls their response to disorder. As such, it reveals the interplay of trapping geometry and disorder in these resonances. The dynamics of the modal coefficientC0(t) as well as that of the phase-mismatchδ(t) between theC0(t) andC1(t) are examined at and away from PR. At PR, |C0(t)| is generally found to be lower in magnitude than away from it, demonstrating that the atoms leave then= 0 ground state towards higher states. In the harmonic oscillator trap, the dynamic pattern ofδ(t) is found to be quite robust against changes in the disorder strength contrary to the box potential. This is because in the box the ratio of the random-potential and kinetic energies is higher than in the harmonic trap signaling that the influence of disorder is weaker in the latter.
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Affiliation(s)
- Roger R Sakhel
- Department of Physics, Faculty of Science, Isra University, Amman 11622, Jordan
| | - Asaad R Sakhel
- Department of Physics, Faculty of Science, Balqa Applied University, Salt 19117, Jordan
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10
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Plestid R, Mahon P, O'Dell DHJ. Violent relaxation in quantum fluids with long-range interactions. Phys Rev E 2018; 98:012112. [PMID: 30110820 DOI: 10.1103/physreve.98.012112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Indexed: 06/08/2023]
Abstract
Violent relaxation is a process that occurs in systems with long-range interactions. It has the peculiar feature of dramatically amplifying small perturbations, and rather than driving the system to equilibrium, it instead leads to slowly evolving configurations known as quasistationary states that fall outside the standard paradigm of statistical mechanics. Violent relaxation was originally identified in gravity-driven stellar dynamics; here, we extend the theory into the quantum regime by developing a quantum version of the Hamiltonian mean field (HMF) model which exemplifies many of the generic properties of long-range interacting systems. The HMF model can either be viewed as describing particles interacting via a cosine potential, or equivalently as the kinetic XY model with infinite-range interactions, and its quantum fluid dynamics can be obtained from a generalized Gross-Pitaevskii equation. We show that singular caustics that form during violent relaxation are regulated by interference effects in a universal way described by Thom's catastrophe theory applied to waves and this leads to emergent length scales and timescales not present in the classical problem. In the deep quantum regime we find that violent relaxation is suppressed altogether by quantum zero-point motion. Our results are relevant to laboratory studies of self-organization in cold atomic gases with long-range interactions.
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Affiliation(s)
- Ryan Plestid
- Department of Physics and Astronomy, McMaster University, 1280 Main St. W. Hamilton, Ontario, Canada L8S 4M1
- Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, Ontario, Canada N2L 2Y5
| | - Perry Mahon
- Department of Physics and Astronomy, McMaster University, 1280 Main St. W. Hamilton, Ontario, Canada L8S 4M1
- Department of Physics, University of Toronto, 60 St. George St., Toronto, Ontario, Canada M5S 1A7
| | - D H J O'Dell
- Department of Physics and Astronomy, McMaster University, 1280 Main St. W. Hamilton, Ontario, Canada L8S 4M1
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11
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Michel C, Boughdad O, Albert M, Larré PÉ, Bellec M. Superfluid motion and drag-force cancellation in a fluid of light. Nat Commun 2018; 9:2108. [PMID: 29844314 PMCID: PMC5974130 DOI: 10.1038/s41467-018-04534-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 05/04/2018] [Indexed: 11/17/2022] Open
Abstract
Quantum fluids of light merge many-body physics and nonlinear optics, revealing quantum hydrodynamic features of light when it propagates in nonlinear media. One of the most outstanding evidence of light behaving as an interacting fluid is its ability to carry itself as a superfluid. Here, we report a direct experimental detection of the transition to superfluidity in the flow of a fluid of light past an obstacle in a bulk nonlinear crystal. In this cavityless all-optical system, we extract a direct optical analog of the drag force exerted by the fluid of light and measure the associated displacement of the obstacle. Both quantities drop to zero in the superfluid regime characterized by a suppression of long-range radiation from the obstacle. The experimental capability to shape both the flow and the potential landscape paves the way for simulation of quantum transport in complex systems.
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Affiliation(s)
- Claire Michel
- Institut de Physique de Nice, Université Côte d'Azur, CNRS, Nice, France.
| | - Omar Boughdad
- Institut de Physique de Nice, Université Côte d'Azur, CNRS, Nice, France
| | - Mathias Albert
- Institut de Physique de Nice, Université Côte d'Azur, CNRS, Nice, France
| | - Pierre-Élie Larré
- Laboratoire de Physique Théorique et Modélisation, Université de Cergy-Pontoise, CNRS, 2 Avenue Adolphe-Chauvin, 95302, Cergy-Pontoise CEDEX, France
- Laboratoire Kastler Brossel, Sorbonne Université, CNRS, ENS-Université PSL, Collège de France, 4 Place Jussieu, 75252, Paris, CEDEX 05, France
| | - Matthieu Bellec
- Institut de Physique de Nice, Université Côte d'Azur, CNRS, Nice, France.
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12
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Non-Linear Stationary Solutions in Realistic Models for Analog Black-Hole Lasers. UNIVERSE 2017. [DOI: 10.3390/universe3030054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Marino J, Recati A, Carusotto I. Casimir Forces and Quantum Friction from Ginzburg Radiation in Atomic Bose-Einstein Condensates. PHYSICAL REVIEW LETTERS 2017; 118:045301. [PMID: 28186806 DOI: 10.1103/physrevlett.118.045301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Indexed: 06/06/2023]
Abstract
We theoretically propose an experimentally viable scheme to use an impurity atom in an atomic Bose-Einstein condensate, in order to realize condensed-matter analogs of quantum vacuum effects. In a suitable atomic level configuration, the collisional interaction between the impurity atom and the density fluctuations in the condensate can be tailored to closely reproduce the electric-dipole coupling of quantum electrodynamics. By virtue of this analogy, we recover and extend the paradigm of electromagnetic vacuum forces to the domain of cold atoms, showing in particular the emergence, at supersonic atomic speeds, of a novel power-law scaling of the Casimir force felt by the atomic impurity, as well as the occurrence of a quantum frictional force, accompanied by the Ginzburg emission of Bogoliubov quanta. Observable consequences of these quantum vacuum effects in realistic spectroscopic experiments are discussed.
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Affiliation(s)
- Jamir Marino
- Institute of Theoretical Physics, TU Dresden, D-01062 Dresden, Germany
- Institute of Theoretical Physics, University of Cologne, D-50937 Cologne, Germany
| | - Alessio Recati
- Physik Department, TU München, James-Franck-Straße 1, 85748 Garching, Germany
- INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, 38123 Povo, Italy
| | - Iacopo Carusotto
- INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, 38123 Povo, Italy
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14
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Iacocca E, Silva TJ, Hoefer MA. Breaking of Galilean Invariance in the Hydrodynamic Formulation of Ferromagnetic Thin Films. PHYSICAL REVIEW LETTERS 2017; 118:017203. [PMID: 28106421 DOI: 10.1103/physrevlett.118.017203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Indexed: 06/06/2023]
Abstract
Microwave magnetodynamics in ferromagnets are often studied in the small-amplitude or weakly nonlinear regime corresponding to modulations of a well-defined magnetic state. However, strongly nonlinear regimes, where the aforementioned approximations are not applicable, have become experimentally accessible. By reinterpreting the governing Landau-Lifshitz equation of motion, we derive an exact set of equations of dispersive hydrodynamic form that are amenable to analytical study even when full nonlinearity and exchange dispersion are included. The resulting equations are shown to, in general, break Galilean invariance. A magnetic Mach number is obtained as a function of static and moving reference frames. The simplest class of solutions are termed uniform hydrodynamic states (UHSs), which exhibit fluidlike behavior including laminar flow at subsonic speeds and the formation of a Mach cone and wave fronts at supersonic speeds. A regime of modulational instability is also possible, where the UHS is violently unstable. The hydrodynamic interpretation opens up novel possibilities in magnetic research.
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Affiliation(s)
- Ezio Iacocca
- Department of Applied Mathematics, University of Colorado, Boulder, Colorado 80309-0526, USA
- Department of Physics, Division for Theoretical Physics, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - T J Silva
- National Institute of Standards and Technology, Boulder, Colorado 80305-3328, USA
| | - Mark A Hoefer
- Department of Applied Mathematics, University of Colorado, Boulder, Colorado 80309-0526, USA
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15
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Carusotto I. Superfluid light in bulk nonlinear media. Proc Math Phys Eng Sci 2014; 470:20140320. [PMID: 25197252 PMCID: PMC4123774 DOI: 10.1098/rspa.2014.0320] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 06/11/2014] [Indexed: 11/12/2022] Open
Abstract
We review how the paraxial approximation naturally leads to a hydrodynamic description of light propagation in a bulk Kerr nonlinear medium in terms of a wave equation analogous to the Gross-Pitaevskii equation for the order parameter of a superfluid. The main features of the many-body collective dynamics of the fluid of light in this propagating geometry are discussed: generation and observation of Bogoliubov sound waves in the fluid of light is first described. Experimentally accessible manifestations of superfluidity are then highlighted. Perspectives in view of realizing analogue models of gravity are finally given.
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Affiliation(s)
- Iacopo Carusotto
- INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, via Sommarive 14, Povo 38123, Italy
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16
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Kamchatnov AM, Kartashov YV. Oblique breathers generated by a flow of two-component Bose-Einstein condensates past a polarized obstacle. PHYSICAL REVIEW LETTERS 2013; 111:140402. [PMID: 24138228 DOI: 10.1103/physrevlett.111.140402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Indexed: 06/02/2023]
Abstract
We predict that oblique breathers can be generated by a flow of two-component Bose-Einstein condensates past a polarized obstacle that attracts one component of the condensate and repels the other one. The breather exists if intraspecies interaction constants differ from the interspecies interaction constant, and it corresponds to the nonlinear excitation of the so-called polarization mode with domination of the relative motion of the components. Analytical theory is developed for the case of small-amplitude breathers that is in reasonable agreement with the numerical results.
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Affiliation(s)
- A M Kamchatnov
- Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow, 142190, Russia
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17
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Kartashov YV, Kamchatnov AM. Two-dimensional dispersive shock waves in dissipative optical media. OPTICS LETTERS 2013; 38:790-792. [PMID: 23455300 DOI: 10.1364/ol.38.000790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We study generation of two-dimensional dispersive shock waves and oblique dark solitons upon interaction of tilted plane waves with negative refractive index defects embedded into defocusing material with linear gain and two-photon absorption. Different evolution regimes are encountered, including the formation of well-localized disturbances for input tilts below critical one, generation of extended shock waves containing multiple intensity oscillations in the "upstream" region, and gradually vanishing oblique dark solitons in the "downstream" region for input tilts exceeding critical one. The generation of stable dispersive shock waves is possible only below certain critical defect strength.
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Affiliation(s)
- Yaroslav V Kartashov
- ICFO-Institut de Ciencies Fotoniques, and Universitat Politecnica de Catalunya, Mediterranean Technology Park, Castelldefels (Barcelona) 08860, Spain.
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18
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Berceanu AC, Cancellieri E, Marchetti FM. Drag in a resonantly driven polariton fluid. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:235802. [PMID: 22588118 DOI: 10.1088/0953-8984/24/23/235802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We study the linear response of a coherently driven polariton fluid in the pump-only configuration scattering against a point-like defect and evaluate analytically the drag force exerted by the fluid on the defect. When the system is excited near the bottom of the lower polariton dispersion, the sign of the interaction-renormalised pump detuning classifies the collective excitation spectra into three different categories (Ciuti and Carusotto 2005 Phys. Status Solidi b 242 2224): linear for zero, diffusive-like for positive and gapped for negative detuning. We show that both cases of zero and positive detuning share a qualitatively similar crossover of the drag force from the subsonic to the supersonic regime as a function of the fluid velocity, with a critical velocity given by the speed of sound found for the linear regime. In contrast, for gapped spectra, we find that the critical velocity exceeds the speed of sound. In all cases, the residual drag force in the subcritical regime depends on the polariton lifetime only. Also, well below the critical velocity, the drag force varies linearly with the polariton lifetime, in agreement with previous work (Cancellieri et al 2010 Phys. Rev. B 82 224512), where the drag was determined numerically for a finite-size defect.
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Affiliation(s)
- A C Berceanu
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
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19
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Amo A, Pigeon S, Sanvitto D, Sala VG, Hivet R, Carusotto I, Pisanello F, Lemenager G, Houdre R, Giacobino E, Ciuti C, Bramati A. Polariton Superfluids Reveal Quantum Hydrodynamic Solitons. Science 2011; 332:1167-70. [DOI: 10.1126/science.1202307] [Citation(s) in RCA: 343] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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20
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Wouters M, Carusotto I. Superfluidity and critical velocities in nonequilibrium Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2010; 105:020602. [PMID: 20867695 DOI: 10.1103/physrevlett.105.020602] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 03/11/2010] [Indexed: 05/29/2023]
Abstract
We theoretically study the superfluidity properties of a nonequilibrium Bose-Einstein condensate of exciton polaritons in a semiconductor microcavity under incoherent pumping. The dynamics of the condensate is described at mean-field level in terms of a generalized Gross-Pitaevskii equation. The drag force on a small moving object and the onset of fringes in the density profile are shown to have a sharp threshold as a function of the velocity; a generalized Landau criterion is developed to explain this behavior in terms of the dispersion of elementary excitations. Metastability of supercurrents in multiply-connected geometries is shown to persist up to higher flow speeds.
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Affiliation(s)
- Michiel Wouters
- Institute of Theoretical Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Sasaki K, Suzuki N, Saito H. Bénard-von Kármán vortex street in a Bose-Einstein condensate. PHYSICAL REVIEW LETTERS 2010; 104:150404. [PMID: 20481976 DOI: 10.1103/physrevlett.104.150404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 03/18/2010] [Indexed: 05/29/2023]
Abstract
Vortex shedding from an obstacle potential moving in a Bose-Einstein condensate is investigated. Long-lived alternately aligned vortex pairs are found to form in the wake, which is similar to the Bénard-von Kármán vortex street in classical viscous fluids. Various patterns of vortex shedding are systematically studied and the drag force on the obstacle is calculated. It is shown that the phenomenon can be observed in a trapped system.
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Affiliation(s)
- Kazuki Sasaki
- Department of Engineering Science, University of Electro-Communications, Tokyo 182-8585, Japan
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22
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Sanvitto D, Amo A, Laussy FP, Lemaître A, Bloch J, Tejedor C, Viña L. Polariton condensates put in motion. NANOTECHNOLOGY 2010; 21:134025. [PMID: 20208103 DOI: 10.1088/0957-4484/21/13/134025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present several examples of the interesting phenomenology shown by a moving polariton condensate in semiconductor microcavities. The superfluid behavior is probed by colliding the polariton condensate against physical obstacles in the form of natural defects of the sample, demonstrating a clear suppression of scattering when the speed of the flow lies below the critical velocity. At higher velocities Cerenkov-like shock waves around the defect and disruption of the condensate are also observed.
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Affiliation(s)
- D Sanvitto
- Departamento de Física de Materiales, Universidad Autónoma de Madrid, Madrid, Spain.
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23
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El GA, Kamchatnov AM, Khodorovskii VV, Annibale ES, Gammal A. Two-dimensional supersonic nonlinear Schrödinger flow past an extended obstacle. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:046317. [PMID: 19905446 DOI: 10.1103/physreve.80.046317] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Indexed: 05/28/2023]
Abstract
Supersonic flow of a superfluid past a slender impenetrable macroscopic obstacle is studied in the framework of the two-dimensional (2D) defocusing nonlinear Schrödinger (NLS) equation. This problem is of fundamental importance as a dispersive analog of the corresponding classical gas-dynamics problem. Assuming the oncoming flow speed is sufficiently high, we asymptotically reduce the original boundary-value problem for a steady flow past a slender body to the one-dimensional dispersive piston problem described by the nonstationary NLS equation, in which the role of time is played by the stretched x coordinate and the piston motion curve is defined by the spatial body profile. Two steady oblique spatial dispersive shock waves (DSWs) spreading from the pointed ends of the body are generated in both half planes. These are described analytically by constructing appropriate exact solutions of the Whitham modulation equations for the front DSW and by using a generalized Bohr-Sommerfeld quantization rule for the oblique dark soliton fan in the rear DSW. We propose an extension of the traditional modulation description of DSWs to include the linear "ship-wave" pattern forming outside the nonlinear modulation region of the front DSW. Our analytic results are supported by direct 2D unsteady numerical simulations and are relevant to recent experiments on Bose-Einstein condensates freely expanding past obstacles.
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Affiliation(s)
- G A El
- Department of Mathematical Sciences, Loughborough University, Loughborough, United Kingdom
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24
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Collective fluid dynamics of a polariton condensate in a semiconductor microcavity. Nature 2009; 457:291-5. [DOI: 10.1038/nature07640] [Citation(s) in RCA: 455] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 11/13/2008] [Indexed: 11/08/2022]
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25
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Kamchatnov AM, Pitaevskii LP. Stabilization of solitons generated by a supersonic flow of Bose-Einstein condensate past an obstacle. PHYSICAL REVIEW LETTERS 2008; 100:160402. [PMID: 18518168 DOI: 10.1103/physrevlett.100.160402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Indexed: 05/26/2023]
Abstract
The stability of dark solitons generated by supersonic flow of a Bose-Einstein condensate past an obstacle is investigated. It is shown that in the reference frame attached to the obstacle a transition occurs at some critical value of the flow velocity from absolute instability of dark solitons to their convective instability. This leads to the decay of disturbances of solitons at a fixed distance from the obstacle and the formation of effectively stable dark solitons. This phenomenon explains the surprising stability of the flow picture that has been observed in numerical simulations.
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Affiliation(s)
- A M Kamchatnov
- Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow Region, 142190, Russia
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26
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Engels P, Atherton C. Stationary and nonstationary fluid flow of a bose-einstein condensate through a penetrable barrier. PHYSICAL REVIEW LETTERS 2007; 99:160405. [PMID: 17995227 DOI: 10.1103/physrevlett.99.160405] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 06/19/2007] [Indexed: 05/25/2023]
Abstract
We experimentally study the fluid flow induced by a broad, penetrable barrier moving through an elongated dilute gaseous Bose-Einstein condensate. The barrier is created by a laser beam swept through the condensate, and the resulting dipole potential can be either attractive or repulsive. We examine both cases and find regimes of stable and unstable fluid flow: At slow speeds of the barrier, the fluid flow is steady due to the superfluidity of the condensate. At intermediate speeds, we observe an unsteady regime in which the condensate gets filled with dark solitons. At faster speeds, soliton formation completely ceases, and a remarkable absence of excitation in the condensate is seen again.
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Affiliation(s)
- P Engels
- Washington State University, Department of Physics and Astronomy, Pullman, Washington 99164, USA.
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