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Meng H, Wang J, Fan X, Wang Q, Shao K, Zhao Y, Wang W, Shi Y. Vector gap solitons of spin-orbit-coupled Bose-Einstein condensate in honeycomb optical lattices. Phys Rev E 2023; 108:034215. [PMID: 37849209 DOI: 10.1103/physreve.108.034215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 09/06/2023] [Indexed: 10/19/2023]
Abstract
The combination of the two hot topics of spin-orbit coupling and honeycomb lattices leads to the appearance of fascinating issues. In this paper, we investigate the existence and stability of vector gap solitons of spin-orbit-coupled Bose-Einstein condensates loaded in honeycomb optical lattices. The existence and stability of vector gap solitons are highly sensitive to the properties of interspin and intraspin atomic interaction. We numerically obtain the parametric dependence of the existence of vector gap solitons both in the semi-infinite gap and in the first gap. Since only dynamically stable localized modes in nonlinear systems are likely to be generated and observed in experiments, we examine the stability of the vector gap solitons by using the direct evolution dynamics, and obtain the phase diagram of stable and unstable vector gap solitons on the parameter plane of interspin and intraspin atomic interactions.
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Affiliation(s)
- Hongjuan Meng
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Jing Wang
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Xiaobei Fan
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Qingqing Wang
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Kaihua Shao
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Yuexin Zhao
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Wenyuan Wang
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
| | - Yuren Shi
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China and Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, Northwest Normal University, Lanzhou 730070, China
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Luo X, Cai Y, Yue X, Zhang Y, Yun F, Li F. Full characterization of vector eigenstates in symmetrically confined systems with photonic spin-orbit coupling. OPTICS EXPRESS 2023; 31:27749-27760. [PMID: 37710843 DOI: 10.1364/oe.495899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/22/2023] [Indexed: 09/16/2023]
Abstract
The photonic spin-orbit (SO) coupling is a widely investigated effect in optical microcavities leading to various interesting physical phenomena and potential applications. We report the full sets of eigenenergies and eigenstates in a symmetrically confined potential under the effect of SO coupling induced by the transverse-electric transverse-magnetic (TE-TM) splitting, which are derived analytically via the degenerate perturbation theory. We obtained the eigenenergies and the eigenstates from the 1st to the 6th orders of excited manifold, and demonstrate unambiguously that universal rules governing the mode formation exist in such complicated photonic systems, making the modes exhibiting the features of solid and hollow skyrmions as well as spin vortices. We show that these eigenstates can be described by the SO coupled hyperspheres that can be decomposed into a series of higher-order Poincare spheres. Our results significantly extend the area of microcavity spin-optronics to the general theory of eigenvalues in confined systems, and provide an efficient theoretical frame for the information processing using microcavity-based high-dimensional vector states.
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Martone GI, Cherroret N. Time Translation Symmetry Breaking in an Isolated Spin-Orbit-Coupled Fluid of Light. PHYSICAL REVIEW LETTERS 2023; 131:013803. [PMID: 37478429 DOI: 10.1103/physrevlett.131.013803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 05/14/2023] [Accepted: 06/08/2023] [Indexed: 07/23/2023]
Abstract
We study the interplay between intrinsic spin-orbit coupling and nonlinear photon-photon interactions in a nonparaxial, elliptically polarized fluid of light propagating in a bulk Kerr medium. We find that in situations where the nonlinear interactions induce birefringence, i.e., a polarization-dependent nonlinear refractive index, their interplay with spin-orbit coupling results in an interference between the two polarization components of the fluid traveling at different wave vectors, which entails the breaking of translation symmetry along the propagation direction. This phenomenon leads to a Floquet band structure in the Bogoliubov spectrum of the fluid, and to characteristic oscillations of its intensity correlations. We characterize these oscillations in detail and point out their exponential growth at large propagation distances, revealing the presence of parametric resonances.
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Affiliation(s)
- Giovanni I Martone
- Laboratoire Kastler Brossel, Sorbonne Université, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, 75005 Paris, France
- CNR NANOTEC, Institute of Nanotechnology, Via Monteroni, 73100 Lecce, Italy
- INFN, Sezione di Lecce, 73100 Lecce, Italy
| | - Nicolas Cherroret
- Laboratoire Kastler Brossel, Sorbonne Université, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, 75005 Paris, France
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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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Cheng SC, Jheng SD, Chen TW. Half-skyrmions with higher topological quantum numbers in homogeneous exciton-polariton condensates. Phys Rev E 2021; 104:054216. [PMID: 34942800 DOI: 10.1103/physreve.104.054216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 11/17/2021] [Indexed: 11/07/2022]
Abstract
We investigate the topological excitations of half-quantum vortices (HQVs) with higher topological quantum numbers in a homogeneous spinor exciton-polariton condensate pumped by a laser beam and an additional coherent light carrying orbital angular momentum. The spin texture and integrated topological charge can be controlled through the pump. Among these textures, the polaritonic half-skyrmions (or polaritonic merons) can be created with a suitable excitation condition. Moreover, when the pump polarization is in favor of the vortex component of the HQV, there is an inversion of circular polarization (spin flipping) from the center of the HQV towards the edge. The radial flipping position can be manipulated by the pump polarization or power. Finally, we demonstrate that the HQVs can stably exist from the linear stability analysis.
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Affiliation(s)
- Szu-Cheng Cheng
- Department of Optoelectric Physics, Chinese Culture University, Taipei 11114, Taiwan, Republic of China.,Quantum Computation and Information Center, Chinese Culture University, Taipei 11114, Taiwan, Republic of China
| | - Shih-Da Jheng
- Department of Optoelectric Physics, Chinese Culture University, Taipei 11114, Taiwan, Republic of China.,Quantum Computation and Information Center, Chinese Culture University, Taipei 11114, Taiwan, Republic of China
| | - Ting-Wei Chen
- Department of Electrophysics, National Chiayi University, Chiayi City 60004, Taiwan, Republic of China
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Moiré pattern of interference dislocations in condensate of indirect excitons. Nat Commun 2021; 12:1175. [PMID: 33608546 PMCID: PMC7895953 DOI: 10.1038/s41467-021-21353-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 01/15/2021] [Indexed: 11/08/2022] Open
Abstract
Interference patterns provide direct measurement of coherent propagation of matter waves in quantum systems. Superfluidity in Bose-Einstein condensates of excitons can enable long-range ballistic exciton propagation and can lead to emerging long-scale interference patterns. Indirect excitons (IXs) are formed by electrons and holes in separated layers. The theory predicts that the reduced IX recombination enables IX superfluid propagation over macroscopic distances. Here, we present dislocation-like phase singularities in interference patterns produced by condensate of IXs. We analyze how exciton vortices and skyrmions should appear in the interference experiments and show that the observed interference dislocations are not associated with these phase defects. We show that the observed interference dislocations originate from the moiré effect in combined interference patterns of propagating condensate matter waves. The interference dislocations are formed by the IX matter waves ballistically propagating over macroscopic distances. The long-range ballistic IX propagation is the evidence for IX condensate superfluidity.
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Ma X, Kartashov YV, Kavokin A, Schumacher S. Chiral condensates in a polariton hexagonal ring. OPTICS LETTERS 2020; 45:5700-5703. [PMID: 33057263 DOI: 10.1364/ol.405400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 09/17/2020] [Indexed: 06/11/2023]
Abstract
We model the generation of vortex modes in exciton-polariton condensates in semiconductor micropillars, arranged into a hexagonal ring molecule, in the presence of TE-TM splitting. This splitting lifts the degeneracy of azimuthally modulated vortex modes with opposite topological charges supported by this structure, so that a number of non-degenerate vortex states characterized by different combinations of topological charges in two polarization components appears. We present a full bifurcation picture for such vortex modes and show that because they have different energies they can be selectively excited by coherent pump beams with specific frequencies and spatial configurations. At high pumping intensity, polariton-polariton interactions give rise to the coupling of different vortex resonances and a bistable regime is achieved.
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Multivalley engineering in semiconductor microcavities. Sci Rep 2017; 7:45243. [PMID: 28367953 PMCID: PMC5377251 DOI: 10.1038/srep45243] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 02/20/2017] [Indexed: 11/27/2022] Open
Abstract
We consider exciton-photon coupling in semiconductor microcavities in which separate periodic potentials have been embedded for excitons and photons. We show theoretically that this system supports degenerate ground-states appearing at non-zero inplane momenta, corresponding to multiple valleys in reciprocal space, which are further separated in polarization corresponding to a polarization-valley coupling in the system. Aside forming a basis for valleytronics, the multivalley dispersion is predicted to allow for spontaneous momentum symmetry breaking and two-mode squeezing under non-resonant and resonant excitation, respectively.
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Dufferwiel S, Li F, Cancellieri E, Giriunas L, Trichet AAP, Whittaker DM, Walker PM, Fras F, Clarke E, Smith JM, Skolnick MS, Krizhanovskii DN. Spin Textures of Exciton-Polaritons in a Tunable Microcavity with Large TE-TM Splitting. PHYSICAL REVIEW LETTERS 2015; 115:246401. [PMID: 26705642 DOI: 10.1103/physrevlett.115.246401] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Indexed: 06/05/2023]
Abstract
We report an extended family of spin textures of zero-dimensional exciton-polaritons spatially confined in tunable open microcavity structures. The transverse-electric-transverse-magnetic (TE-TM) splitting, which is enhanced in the open cavity structures, leads to polariton eigenstates carrying quantized spin vortices. Depending on the strength and anisotropy of the cavity confining potential and of the TE-TM induced splitting, which can be tuned via the excitonic or photonic fractions, the exciton-polariton emissions exhibit either spin-vortex-like patterns or linear polarization, in good agreement with theoretical modeling.
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Affiliation(s)
- S Dufferwiel
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - Feng Li
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - E Cancellieri
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - L Giriunas
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - A A P Trichet
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom
| | - D M Whittaker
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - P M Walker
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - F Fras
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
- IPCMS UMR 7504, CNRS and Université de Strasbourg, 67200 Strasbourg, France
| | - E Clarke
- EPSRC National Centre for III-V Technologies, University of Sheffield, Sheffield S1 3JD, United Kingdom
| | - J M Smith
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom
| | - M S Skolnick
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - D N Krizhanovskii
- Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom
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Nalitov AV, Malpuech G, Terças H, Solnyshkov DD. Spin-orbit coupling and the optical spin Hall effect in photonic graphene. PHYSICAL REVIEW LETTERS 2015; 114:026803. [PMID: 25635557 DOI: 10.1103/physrevlett.114.026803] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Indexed: 06/04/2023]
Abstract
We study the spin-orbit coupling induced by the splitting between TE and TM optical modes in a photonic honeycomb lattice. Using a tight-binding approach, we calculate analytically the band structure. Close to the Dirac point, we derive an effective Hamiltonian. We find that the local reduced symmetry (D_{3h}) transforms the TE-TM effective magnetic field into an emergent field with a Dresselhaus symmetry. As a result, particles become massive, but no gap opens. The emergent field symmetry is revealed by the optical spin Hall effect.
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Affiliation(s)
- A V Nalitov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - G Malpuech
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - H Terças
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - D D Solnyshkov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
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Terças H, Solnyshkov DD, Malpuech G. High-speed DC transport of emergent monopoles in spinor photonic fluids. PHYSICAL REVIEW LETTERS 2014; 113:036403. [PMID: 25083658 DOI: 10.1103/physrevlett.113.036403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Indexed: 06/03/2023]
Abstract
We investigate the spin dynamics of half-solitons in quantum fluids of interacting photons (exciton polaritons). Half-solitons, which behave as emergent monopoles, can be accelerated by the presence of effective magnetic fields. We study the generation of dc magnetic currents in a gas of half-solitons. At low densities, the current is suppressed due to the dipolar oscillations. At moderate densities, a magnetic current is recovered as a consequence of the collisions between the carriers. We show a deviation from Ohm's law due to the competition between dipoles and monopoles.
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Affiliation(s)
- H Terças
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
| | - D D Solnyshkov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
| | - G Malpuech
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
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Egorov OA, Lederer F. Pseudospin-induced motion of cavity polariton soliton molecules. OPTICS LETTERS 2014; 39:4029-4032. [PMID: 24978799 DOI: 10.1364/ol.39.004029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We study the effect of pseudospin precession of exciton-polaritons, known as optical spin Hall effect, on the dynamics of polariton solitons in semiconductor microresonators operating in the strong-coupling regime. We demonstrate that elliptically polarized polariton solitons, coherently driven by a linearly polarized pump, can form robust bound states. Due to spin-to-orbital angular momentum conversion, these polariton soliton molecules move uniformly in the mirror plane provided transverse electric-transverse magnetic mode splitting is taken into account.
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13
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Terças H, Flayac H, Solnyshkov DD, Malpuech G. Non-Abelian gauge fields in photonic cavities and photonic superfluids. PHYSICAL REVIEW LETTERS 2014; 112:066402. [PMID: 24580697 DOI: 10.1103/physrevlett.112.066402] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Indexed: 06/03/2023]
Abstract
We show that the TE-TM modes splitting and the structure anisotropy of a semiconductor microcavity combine into a non-Abelian gauge field for exciton-polaritons or cavity photons. The field texture can be tuned simply by rotating the sample and ranges continuously from a Rashba to a monopolar field. In the noninteracting regime, the latter leads to remarkable focusing and conical diffraction effects. In the interacting regime, the spin-orbit coupling induces a breakdown of superfluidity. The spatially homogeneous flows become unstable and dynamically evolve into spin textured states, such as stripes or domain walls.
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Affiliation(s)
- H Terças
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
| | - H Flayac
- Institute of Theoretical Physics, École Polytechnique Fédérale de Lausanne EPFL, CH-1015 Lausanne, Switzerland
| | - D D Solnyshkov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
| | - G Malpuech
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 Avenue des Landais, 63177 Aubière Cedex, France
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Vishnevsky DV, Flayac H, Nalitov AV, Solnyshkov DD, Gippius NA, Malpuech G. Skyrmion formation and optical spin-Hall effect in an expanding coherent cloud of indirect excitons. PHYSICAL REVIEW LETTERS 2013; 110:246404. [PMID: 25165945 DOI: 10.1103/physrevlett.110.246404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Indexed: 06/03/2023]
Abstract
We provide a theoretical description of the polarization pattern and phase singularities experimentally evidenced recently in a condensate of indirect excitons [H. High et al., Nature 483, 584 (2012)]. We show that the averaging of the electron and hole orbital motion leads to a comparable spin-orbit interaction for both types of carriers. We demonstrate that the interplay between a radial coherent flux of bright indirect excitons and the Dresselhaus spin-orbit interaction results in the formation of spin domains and of topological defects similar to Skyrmions. We reproduce qualitatively all the features of the experimental data and obtain a polarization pattern as in the optical spin-Hall effect despite the different symmetry of the spin-orbit interactions.
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Affiliation(s)
- D V Vishnevsky
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - H Flayac
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - A V Nalitov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - D D Solnyshkov
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
| | - N A Gippius
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France and A. M. Prokhorov General Physics Institute, RAS, Vavilova Street 38, Moscow 119991, Russia
| | - G Malpuech
- Institut Pascal, PHOTON-N2, Clermont Université, Blaise Pascal University, CNRS, 24 avenue des Landais, 63177 Aubière Cedex, France
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