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Luo H, Luo J, Zhang Z, Wu C, Li Q, Liu W, Peng R, Wang M, Li H, Lai Y. Dielectric metamaterials with effective self-duality and full-polarization omnidirectional brewster effect. LIGHT, SCIENCE & APPLICATIONS 2024; 13:262. [PMID: 39300089 DOI: 10.1038/s41377-024-01605-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 08/13/2024] [Accepted: 08/25/2024] [Indexed: 09/22/2024]
Abstract
Conventional dielectric solid materials, both natural and artificial, lack electromagnetic self-duality and thus require additional coatings to achieve impedance matching with free space. Here, we present a class of dielectric metamaterials that are effectively self-dual and vacuum-like, thereby exhibiting full-polarization omnidirectional impedance matching as an unusual Brewster effect extended across all incident angles and polarizations. With both birefringence and reflection eliminated regardless of wavefront and polarization, such anisotropic metamaterials could establish the electromagnetic equivalence with "stretched free space" in transformation optics, as substantiated through full-wave simulations and microwave experiments. Our findings open a practical pathway for realizing unprecedented polarization-independence and omnidirectional impedance-matching characteristics in pure dielectric solids.
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Affiliation(s)
- Hao Luo
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Jie Luo
- School of Physical Science and Technology & Jiangsu key Laboratory of Frontier Material Physics and Devices, Soochow University, Suzhou, 215006, China.
| | - Zhihui Zhang
- School of Physics Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Chao Wu
- College of Electronic and Information Engineering, Tongji University, Shanghai, 200092, China
| | - Quan Li
- College of Electronic and Information Engineering, Tongji University, Shanghai, 200092, China
| | - Wei Liu
- College for Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha, Hunan, 410073, China
| | - Ruwen Peng
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Mu Wang
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Hongqiang Li
- College of Electronic and Information Engineering, Tongji University, Shanghai, 200092, China.
| | - Yun Lai
- National Laboratory of Solid State Microstructures, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
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2
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Wang P, Chen Y, Liu W. Geometric Phase-Driven Scattering Evolutions. PHYSICAL REVIEW LETTERS 2024; 133:093801. [PMID: 39270158 DOI: 10.1103/physrevlett.133.093801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 07/16/2024] [Indexed: 09/15/2024]
Abstract
Conventional approaches for scattering manipulations largely rely on the technique of field expansions into spherical harmonics (electromagnetic multipoles), which nevertheless is not only nongeneric (expansion coefficients depend on the origin position of the coordinate system) but also more descriptive than predictive. Here, we explore this classical topic from a different perspective of controlled excitations and interferences of quasinormal modes (QNMs) supported by the scattering system. Scattered waves are expanded into coherent additions of QNMs, among which the relative amplitudes and phases are crucial factors to architect for scattering manipulations. Relying on the electromagnetic reciprocity, we provide full geometric representations based on the Poincaré sphere for those factors, and discover the hidden geometric phase of QNMs that drives the scattering evolutions. Further synchronous exploitations of the incident polarization-dependent geometric phase and excitation amplitudes enable efficient manipulations of both scattering intensities and polarizations. Continuous geometric phase spanning 2π is directly manifest through scattering variations, even in the rather elementary configuration of an individual particle scattering waves of varying polarizations. We have essentially established a profoundly all-encompassing framework for the calculations of geometric phase in arbitrary scattering systems that are reciprocal. Our theoretical model will greatly broaden horizons of many disciplines not only in photonics but also in general wave physics where geometric phase is generic and ubiquitous.
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3
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Wen C, Zhang J, Qin S, Zhu Z, Liu W. Magneto-chiral backscatterings by rotationally symmetric nonreciprocal structures. OPTICS EXPRESS 2024; 32:17220-17228. [PMID: 38858911 DOI: 10.1364/oe.518884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 04/13/2024] [Indexed: 06/12/2024]
Abstract
It was proved that the joint operation of electromagnetic reciprocity and n-fold (n ≥ 3) rotational symmetry would secure arbitrary polarization-independent backscattering efficiency [Phys. Rev. B103(4), 045422 (2021)10.1103/PhysRevB.103.045422]. Here we remove the restriction of reciprocity and study the backscatterings of plane waves by rotationally symmetric magneto-optical structures, with collinear incident wavevector, rotational axis and externally applied magnetic field. It is revealed that though nonreciprocity removes the degeneracy of backscattering efficiencies for circularly-polarized incident waves of opposite handedness, the remaining rotational symmetry is sufficient to guarantee that the efficiency is related to the polarization ellipticity only, having nothing to do with the orientations of the polarization ellipses. Moreover, the backscattering efficiency reaches its extremes (maximum or minimum values) always for circularly-polarized incident waves, and for other polarizations the efficiency is their ellipticity-weighted arithmetic average. The principles we have revealed are dictated by rotational symmetries only, which are irrelevant to specific geometric or optical parameters and are intrinsically robust against any rotational-symmetry preserving perturbations. The correlations we have discovered could be further exploited for fundamental explorations in nonreciprocal photonics and practical applications including polarimetry and ellipsometry.
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4
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Mohammadi E, Raziman TV, Curto AG. Nanophotonic Chirality Transfer to Dielectric Mie Resonators. NANO LETTERS 2023; 23:3978-3984. [PMID: 37126640 PMCID: PMC10176573 DOI: 10.1021/acs.nanolett.3c00739] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Nanophotonics can boost the weak circular dichroism of chiral molecules. One mechanism for enhanced chiral sensing relies on using a resonator to create fields with high optical chirality at the molecular position. Here, we elucidate how the reverse interaction between molecules and the resonator, called chirality transfer, can produce stronger circular dichroism. The chiral analyte modifies the electric and magnetic dipole moments of the resonator, imprinting a chiral response on an otherwise achiral resonance. We demonstrate that silicon nanoparticles and metasurfaces tailored for chirality transfer generate chiroptical signals orders of magnitude higher than the contribution from optical chirality alone. We derive closed-form equations for the dependence of chirality transfer on molecular chirality, molecule-resonator distance, and Mie coefficients. We propose a dielectric metasurface for a 900-fold circular dichroism enhancement on the basis of these principles. Finally, we identify a fundamental limit to chirality transfer. Our findings thus establish key concepts for nanophotonic chiral sensing.
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Affiliation(s)
- Ershad Mohammadi
- Department of Applied Physics and Eindhoven Hendrik Casimir Institute, Eindhoven University of Technology, 5600MB Eindhoven, The Netherlands
| | - T V Raziman
- Department of Applied Physics and Eindhoven Hendrik Casimir Institute, Eindhoven University of Technology, 5600MB Eindhoven, The Netherlands
| | - Alberto G Curto
- Department of Applied Physics and Eindhoven Hendrik Casimir Institute, Eindhoven University of Technology, 5600MB Eindhoven, The Netherlands
- Photonics Research Group, Ghent University-imec, 9052 Ghent, Belgium
- Center for Nano- and Biophotonics, Ghent University, 9052 Ghent, Belgium
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5
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Zhang Q, He L, Mele EJ, Zhen B, Johnson ATC. General duality and magnet-free passive phononic Chern insulators. Nat Commun 2023; 14:916. [PMID: 36807575 PMCID: PMC9938148 DOI: 10.1038/s41467-023-36420-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/27/2023] [Indexed: 02/19/2023] Open
Abstract
Integrated phononics plays an important role in both fundamental physics and technology. Despite great efforts, it remains a challenge to break time-reversal symmetry to achieve topological phases and non-reciprocal devices. Piezomagnetic materials offer an intriguing opportunity as they break time-reversal symmetry intrinsically, without the need for an external magnetic field or an active driving field. Moreover, they are antiferromagnetic, and possibly compatible with superconducting components. Here, we develop a theoretical framework that combines linear elasticity with Maxwell's equations via piezoelectricity and/or piezomagnetism beyond the commonly adopted quasi-static approximation. Our theory predicts and numerically demonstrates phononic Chern insulators based on piezomagnetism. We further show that the topological phase and chiral edge states in this system can be controlled by the charge doping. Our results exploit a general duality relation between piezoelectric and piezomagnetic systems, which can potentially be generalized to other composite metamaterial systems.
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Affiliation(s)
- Qicheng Zhang
- grid.25879.310000 0004 1936 8972Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Li He
- grid.25879.310000 0004 1936 8972Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Eugene J. Mele
- grid.25879.310000 0004 1936 8972Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Bo Zhen
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - A. T. Charlie Johnson
- grid.25879.310000 0004 1936 8972Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA ,grid.25879.310000 0004 1936 8972Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104 USA
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6
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Stamatopoulou PE, Droulias S, Acuna GP, Mortensen NA, Tserkezis C. Reconfigurable chirality with achiral excitonic materials in the strong-coupling regime. NANOSCALE 2022; 14:17581-17588. [PMID: 36408680 DOI: 10.1039/d2nr05063c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
We introduce and theoretically analyze the concept of manipulating optical chirality via strong coupling of the optical modes of chiral nanostructures with excitonic transitions in molecular layers or semiconductors. With chirality being omnipresent in chemistry and biomedicine, and highly desirable for technological applications related to efficient light manipulation, the design of nanophotonic architectures that sense the handedness of molecules or generate the desired light polarization in an externally controllable manner is of major interdisciplinary importance. Here we propose that such capabilities can be provided by the mode splitting resulting from polaritonic hybridization. Starting with an object with well-known chiroptical response-here, for a proof of concept, a chiral sphere-we show that strong coupling with a nearby excitonic material generates two spectral branches that retain the object's high chirality density, which manifest most clearly through anticrossings in circular-dichroism or differential-scattering dispersion diagrams. These windows can be controlled by the intrinsic properties of the excitonic layer and the strength of the interaction, enabling thus the post-fabrication manipulation of optical chirality. Our findings are further verified via simulations of circular dichroism of a realistic chiral architecture, namely a helical assembly of plasmonic nanospheres embedded in a resonant matrix.
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Affiliation(s)
- P Elli Stamatopoulou
- Center for Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Sotiris Droulias
- Department of Digital Systems, University of Piraeus, GR-18534, Piraeus, Greece
| | - Guillermo P Acuna
- Department of Physics, University of Fribourg, Chemin du Musée 3, Fribourg CH-1700, Switzerland
| | - N Asger Mortensen
- Center for Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
- Danish Institute for Advanced Study, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Christos Tserkezis
- Center for Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
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7
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Yang Q, Chen W, Chen Y, Liu W. Ideal Kerker scattering by homogeneous spheres: the role of gain or loss. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2022; 13:828-835. [PMID: 36105694 PMCID: PMC9443427 DOI: 10.3762/bjnano.13.73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
We investigate how the optical gain or loss (characterized by isotropic complex refractive indexes) influence the ideal Kerker scattering of exactly zero backward scattering. It was previously shown that, for non-magnetic homogeneous spheres with incident plane waves, either gain or loss prohibit ideal Kerker scattering, provided that only electric and magnetic multipoles of a specific order are present and contributions from other multipoles can all be made precisely zero. Here we reveal that, when two multipoles of a fixed order are perfectly matched in terms of both phase and magnitude, multipoles of at least the next two orders cannot possibly be tuned to be all precisely zero or even perfectly matched, and consequently cannot directly produce ideal Kerker scattering. Moreover, we further demonstrate that, when multipoles of different orders are simultaneously taken into consideration, loss or gain can serve as helpful rather than harmful contributing factors, for the elimination of backward scattering.
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Affiliation(s)
- Qingdong Yang
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
| | - Weijin Chen
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
| | - Yuntian Chen
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
| | - Wei Liu
- College for Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha, Hunan 410073, P. R. China
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8
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Bliokh KY, Bliokh YP. Momentum, angular momentum, and spin of waves in an isotropic collisionless plasma. Phys Rev E 2022; 105:065208. [PMID: 35854583 DOI: 10.1103/physreve.105.065208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
We examine the momentum and angular momentum (including spin) properties of linear waves, both longitudinal (Langmuir) and transverse (electromagnetic), in an isotropic nonrelativistic collisionless electron plasma. We focus on conserved quantities associated with the translational and rotational invariance of the wave fields with respect to the homogeneous medium; these are sometimes called pseudomomenta. There are two types of the momentum and angular momentum densities: (i) the kinetic ones associated with the energy flux density and the symmetrized (Belinfante) energy-momentum tensor and (ii) the canonical ones associated with the conserved Noether currents and canonical energy-momentum tensor. We find that the canonical momentum and spin densities of Langmuir waves are similar to those of sound waves in fluids or gases; they are naturally expressed via the electron velocity field. In turn, the momentum and spin densities of electromagnetic waves can be written either in the forms known for free-space electromagnetic fields, involving only the electric field, or in the dual-symmetric forms involving both electric and magnetic fields, as well as the effective permittivity of plasma. We derive these properties both within the phenomenological macroscopic approach and microscopic Lagrangian field theory for the coupled electromagnetic fields and electrons. Finally, we explore implications of the canonical momentum and spin densities in transport and electrodynamic phenomena: the Stokes drift, the wave-induced magnetization (inverse Faraday effect), etc.
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Affiliation(s)
- Konstantin Y Bliokh
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama 351-0198, Japan
| | - Yury P Bliokh
- Physics Department, Technion, Israel Institute of Technology, Haifa 320003, Israel
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9
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Lei QL, Zheng W, Tang F, Wan X, Ni R, Ma YQ. Self-Assembly of Isostatic Self-Dual Colloidal Crystals. PHYSICAL REVIEW LETTERS 2021; 127:018001. [PMID: 34270286 DOI: 10.1103/physrevlett.127.018001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/01/2021] [Indexed: 06/13/2023]
Abstract
Self-dual structures whose dual counterparts are themselves possess unique hidden symmetry, beyond the description of classical spatial symmetry groups. Here we propose a strategy based on a nematic monolayer of attractive half-cylindrical colloids to self-assemble these exotic structures. This system can be seen as a 2D system of semidisks. By using Monte Carlo simulations, we discover two isostatic self-dual crystals, i.e., an unreported crystal with pmg space-group symmetry and the twisted kagome crystal. For the pmg crystal approaching the critical point, we find the double degeneracy of the full phononic spectrum at the self-dual point and the merging of two tilted Weyl nodes into one critically tilted Dirac node. The latter is "accidentally" located on the high-symmetry line. The formation of this unconventional Dirac node is due to the emergence of the critical flatbands at the self-dual point, which are linear combinations of "finite-frequency" floppy modes. These modes can be understood as mechanically coupled self-dual rhombus chains vibrating in some unique uncoupled ways. Our work paves the way for designing and fabricating self-dual materials with exotic mechanical or phononic properties.
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Affiliation(s)
- Qun-Li Lei
- National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 Singapore
| | - Wei Zheng
- National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 Singapore
| | - Feng Tang
- National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Xiangang Wan
- National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Ran Ni
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 Singapore
| | - Yu-Qiang Ma
- National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
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10
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Mohammadi E, Tittl A, Tsakmakidis KL, Raziman TV, Curto AG. Dual Nanoresonators for Ultrasensitive Chiral Detection. ACS PHOTONICS 2021; 8:1754-1762. [PMID: 34164565 PMCID: PMC8213055 DOI: 10.1021/acsphotonics.1c00311] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Indexed: 05/19/2023]
Abstract
The discrimination of enantiomers is crucial in biochemistry. However, chiral sensing faces significant limitations due to inherently weak chiroptical signals. Nanophotonics is a promising solution to enhance sensitivity thanks to increased optical chirality maximized by strong electric and magnetic fields. Metallic and dielectric nanoparticles can separately provide electric and magnetic resonances. Here we propose their synergistic combination in hybrid metal-dielectric nanostructures to exploit their dual character for superchiral fields beyond the limits of single particles. For optimal optical chirality, in addition to maximization of the resonance strength, the resonances must spectrally coincide. Simultaneously, their electric and magnetic fields must be parallel and π/2 out of phase and spatially overlap. We demonstrate that the interplay between the strength of the resonances and these optimal conditions constrains the attainable optical chirality in resonant systems. Starting from a simple symmetric nanodimer, we derive closed-form expressions elucidating its fundamental limits of optical chirality. Building on the trade-offs of different classes of dimers, we then suggest an asymmetric dual dimer based on realistic materials. These dual nanoresonators provide strong and decoupled electric and magnetic resonances together with optimal conditions for chiral fields. Finally, we introduce more complex dual building blocks for a metasurface with a record 300-fold enhancement of local optical chirality in nanoscale gaps, enabling circular dichroism enhancement by a factor of 20. By combining analytical insight and practical designs, our results put forward hybrid resonators to increase chiral sensitivity, particularly for small molecular quantities.
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Affiliation(s)
- Ershad Mohammadi
- Department
of Applied Physics and Institute for Photonic Integration, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| | - Andreas Tittl
- Chair
in Hybrid Nanosystems, Nanoinstitute Munich, Faculty of Physics, Ludwig-Maximilians-Universität München, 80539 Munich, Germany
| | - Kosmas L. Tsakmakidis
- Section
of Condensed Matter Physics, Department of Physics, National and Kapodistrian University of Athens, Panepistimioupolis, GR-157 84 Athens, Greece
| | - T. V. Raziman
- Department
of Applied Physics and Institute for Photonic Integration, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| | - Alberto G. Curto
- Department
of Applied Physics and Institute for Photonic Integration, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
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11
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Hou SS, Liu Y, Zhang WX, Zhang XD. Separating and trapping of chiral nanoparticles with dielectric photonic crystal slabs. OPTICS EXPRESS 2021; 29:15177-15189. [PMID: 33985222 DOI: 10.1364/oe.423243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
Chiral separation is a crucial step in many chemical synthesis processes, particularly for pharmaceuticals. Here we present a novel method for the realization of both separating and trapping of enantiomers using the dielectric photonic crystal (PhC) slabs, which possess quasi-fourfold degenerate Bloch modes (overlapping double degenerate transverse-electric-like and transverse-magnetic-like modes). Based on the designed structure, a large gradient of optical chirality appears near the PhC slab, leading to the extreme enhancement of chiral optical forces about 3 orders of magnitude larger than those obtained with circularly polarized lights. In this case, our method provides a reference for realizing all-optical enantiopure syntheses.
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12
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Effects of symmetry-breaking on electromagnetic backscattering. Sci Rep 2021; 11:1721. [PMID: 33462280 PMCID: PMC7814122 DOI: 10.1038/s41598-020-80347-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 12/16/2020] [Indexed: 11/22/2022] Open
Abstract
Systems with a discrete rotational symmetry \documentclass[12pt]{minimal}
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\begin{document}$$2\pi /n$$\end{document}2π/n where \documentclass[12pt]{minimal}
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\begin{document}$$n\ge 3$$\end{document}n≥3 that also have electromagnetic duality symmetry exhibit zero backscattering. The impact of breaking one of the two symmetries on the emerging backscattering has not yet been systematically studied. Here, we investigate the effect that perturbatively breaking each of the two symmetries has on the backscattering off individual objects and 2D arrays. We find that the backscattering off electromagnetically-small prisms increases with the parameters that determine the symmetry breaking, and that the increase of the backscattering due to the progressive breaking of one of the symmetries can be related to the other symmetry. Further exploration of the interplay between the two symmetries reveals that, in systems lacking enough rotational symmetry, the backscattering can be almost-entirely suppressed for a given linear polarization by deliberately breaking the duality symmetry. This duality breaking can be interpreted as an effective increase of the electromagnetic degree of rotational symmetry for that linear polarization.
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13
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Mun J, Kim M, Yang Y, Badloe T, Ni J, Chen Y, Qiu CW, Rho J. Electromagnetic chirality: from fundamentals to nontraditional chiroptical phenomena. LIGHT, SCIENCE & APPLICATIONS 2020; 9:139. [PMID: 32922765 PMCID: PMC7463035 DOI: 10.1038/s41377-020-00367-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 06/25/2020] [Accepted: 07/08/2020] [Indexed: 05/05/2023]
Abstract
Chirality arises universally across many different fields. Recent advancements in artificial nanomaterials have demonstrated chiroptical responses that far exceed those found in natural materials. Chiroptical phenomena are complicated processes that involve transitions between states with opposite parities, and solid interpretations of these observations are yet to be clearly provided. In this review, we present a comprehensive overview of the theoretical aspects of chirality in light, nanostructures, and nanosystems and their chiroptical interactions. Descriptions of observed chiroptical phenomena based on these fundamentals are intensively discussed. We start with the strong intrinsic and extrinsic chirality in plasmonic nanoparticle systems, followed by enantioselective sensing and optical manipulation, and then conclude with orbital angular momentum-dependent responses. This review will be helpful for understanding the mechanisms behind chiroptical phenomena based on underlying chiral properties and useful for interpreting chiroptical systems for further studies.
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Affiliation(s)
- Jungho Mun
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
| | - Minkyung Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
| | - Younghwan Yang
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
| | - Trevon Badloe
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
| | - Jincheng Ni
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583 Singapore
| | - Yang Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583 Singapore
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583 Singapore
| | - Junsuk Rho
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, 37673 Korea
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14
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Olmos-Trigo J, Sanz-Fernández C, Abujetas DR, Lasa-Alonso J, de Sousa N, García-Etxarri A, Sánchez-Gil JA, Molina-Terriza G, Sáenz JJ. Kerker Conditions upon Lossless, Absorption, and Optical Gain Regimes. PHYSICAL REVIEW LETTERS 2020; 125:073205. [PMID: 32857534 DOI: 10.1103/physrevlett.125.073205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
The directionality and polarization of light show peculiar properties when the scattering by a dielectric sphere can be described exclusively by electric and magnetic dipolar modes. Particularly, when these modes oscillate in phase with equal amplitude, at the so-called first Kerker condition, the zero optical backscattering condition emerges for nondissipating spheres. However, the role of absorption and optical gain in the first Kerker condition remains unexplored. In this work, we demonstrate that either absorption or optical gain precludes the first Kerker condition and, hence, the absence of backscattered radiation light, regardless of the particle's size, incident wavelength, and incoming polarization. Finally, we derive the necessary prerequisites of the second Kerker condition of the zero forward light scattering, finding that optical gain is a compulsory requirement.
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Affiliation(s)
- Jorge Olmos-Trigo
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
| | - Cristina Sanz-Fernández
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - Diego R Abujetas
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Instituto de Estructura de la Materia (IEM-CSIC), Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid, Spain
| | - Jon Lasa-Alonso
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - Nuno de Sousa
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
| | - Aitzol García-Etxarri
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - José A Sánchez-Gil
- Instituto de Estructura de la Materia (IEM-CSIC), Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid, Spain
| | - Gabriel Molina-Terriza
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, 20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Juan José Sáenz
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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15
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Feis J, Beutel D, Köpfler J, Garcia-Santiago X, Rockstuhl C, Wegener M, Fernandez-Corbaton I. Helicity-Preserving Optical Cavity Modes for Enhanced Sensing of Chiral Molecules. PHYSICAL REVIEW LETTERS 2020; 124:033201. [PMID: 32031847 DOI: 10.1063/5.0025006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 11/13/2020] [Indexed: 05/20/2023]
Abstract
Researchers routinely sense molecules by their infrared vibrational "fingerprint" absorption resonances. In addition, the dominant handedness of chiral molecules can be detected by circular dichroism (CD), the normalized difference between their optical response to incident left- and right- handed circularly polarized light. Here, we introduce a cavity composed of two parallel arrays of helicity-preserving silicon disks that allows one to enhance the CD signal by more than 2 orders of magnitude for a given molecule concentration and given thickness of the cell containing the molecules. The underlying principle is first-order diffraction into helicity-preserving modes with large transverse momentum and long lifetimes. In sharp contrast, in a conventional Fabry-Perot cavity, each reflection flips the handedness of light, leading to large intensity enhancements inside the cavity, yet to smaller CD signals than without the cavity.
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Affiliation(s)
- Joshua Feis
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Dominik Beutel
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Julian Köpfler
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Xavier Garcia-Santiago
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- JCMWave GmbH, 14050 Berlin, Germany
| | - Carsten Rockstuhl
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Martin Wegener
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
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16
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Feis J, Beutel D, Köpfler J, Garcia-Santiago X, Rockstuhl C, Wegener M, Fernandez-Corbaton I. Helicity-Preserving Optical Cavity Modes for Enhanced Sensing of Chiral Molecules. PHYSICAL REVIEW LETTERS 2020; 124:033201. [PMID: 32031847 DOI: 10.1103/physrevlett.124.033201] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Indexed: 05/20/2023]
Abstract
Researchers routinely sense molecules by their infrared vibrational "fingerprint" absorption resonances. In addition, the dominant handedness of chiral molecules can be detected by circular dichroism (CD), the normalized difference between their optical response to incident left- and right- handed circularly polarized light. Here, we introduce a cavity composed of two parallel arrays of helicity-preserving silicon disks that allows one to enhance the CD signal by more than 2 orders of magnitude for a given molecule concentration and given thickness of the cell containing the molecules. The underlying principle is first-order diffraction into helicity-preserving modes with large transverse momentum and long lifetimes. In sharp contrast, in a conventional Fabry-Perot cavity, each reflection flips the handedness of light, leading to large intensity enhancements inside the cavity, yet to smaller CD signals than without the cavity.
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Affiliation(s)
- Joshua Feis
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Dominik Beutel
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
| | - Julian Köpfler
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Xavier Garcia-Santiago
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- JCMWave GmbH, 14050 Berlin, Germany
| | - Carsten Rockstuhl
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Martin Wegener
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
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17
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The Pre-Potential of a Field Propagating with the Speed of Light and Its Dual Symmetry. Symmetry (Basel) 2019. [DOI: 10.3390/sym11121430] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Relativity theory assumes that force fields propagate with the speed of light. We show that such force fields generated by a single source can be described by a pre-potential, which is a complex-valued function on spacetime outside the worldline of the source. The pre-potential is invariant under a spin-half representation of the Lorentz group acting on complexified spacetime. The complex four-potential of such a field is defined and calculated explicitly from the pre-potential without assuming any particular force law for the field. The real part of the obtained four-potential coincides with the known Liénard–Wiechert potential. The symmetry of the four-potential is described herein. The pre-potential satisfies the wave equation. The single source electromagnetic field derived from this four-potential is self-dual or anti-self-dual. The pre-potential and the four-potential are extended to a field with several sources.
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18
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Abstract
The average helicity of a given electromagnetic field measures the difference between the number of left- and right-handed photons contained in the field. Here, the average helicity is derived using the conformally invariant inner product for Maxwell fields. Several equivalent integral expressions in momentum space, in ( r , t ) space, and in the time-harmonic ( r , ω ) space are obtained, featuring Riemann–Silberstein-like fields and potentials. The time-harmonic expressions can be directly evaluated using the outputs of common numerical solvers of Maxwell equations. The results are shown to be equivalent to the well-known volume integral for the average helicity, featuring the electric and magnetic fields and potentials.
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19
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Geometric Structure behind Duality and Manifestation of Self-Duality from Electrical Circuits to Metamaterials. Symmetry (Basel) 2019. [DOI: 10.3390/sym11111336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In electromagnetic systems, duality is manifested in various forms: circuit, Keller–Dykhne, electromagnetic, and Babinet dualities. These dualities have been developed individually in different research fields and frequency regimes, leading to a lack of unified perspective. In this paper, we establish a unified view of these dualities in electromagnetic systems. The underlying geometrical structures behind the dualities are elucidated by using concepts from algebraic topology and differential geometry. Moreover, we show that seemingly disparate phenomena, such as frequency-independent effective response, zero backscattering, and critical response, can be considered to be emergent phenomena of self-duality.
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20
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Optical Helicity and Optical Chirality in Free Space and in the Presence of Matter. Symmetry (Basel) 2019. [DOI: 10.3390/sym11091113] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The inherently weak nature of chiral light–matter interactions can be enhanced by orders of magnitude utilizing artificially-engineered nanophotonic structures. These structures enable high spatial concentration of electromagnetic fields with controlled helicity and chirality. However, the effective design and optimization of nanostructures requires defining physical observables which quantify the degree of electromagnetic helicity and chirality. In this perspective, we discuss optical helicity, optical chirality, and their related conservation laws, describing situations in which each provides the most meaningful physical information in free space and in the context of chiral light–matter interactions. First, an instructive comparison is drawn to the concepts of momentum, force, and energy in classical mechanics. In free space, optical helicity closely parallels momentum, whereas optical chirality parallels force. In the presence of macroscopic matter, the optical helicity finds its optimal physical application in the case of lossless, dual-symmetric media, while, in contrast, the optical chirality provides physically observable information in the presence of lossy, dispersive media. Finally, based on numerical simulations of a gold and silicon nanosphere, we discuss how metallic and dielectric nanostructures can generate chiral electromagnetic fields upon interaction with chiral light, offering guidelines for the rational design of nanostructure-enhanced electromagnetic chirality.
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21
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Fernandez-Corbaton I, Rockstuhl C, Ziemke P, Gumbsch P, Albiez A, Schwaiger R, Frenzel T, Kadic M, Wegener M. New Twists of 3D Chiral Metamaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1807742. [PMID: 30790363 DOI: 10.1002/adma.201807742] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Indexed: 06/09/2023]
Abstract
Rationally designed artificial materials, called metamaterials, allow for tailoring effective material properties beyond ("meta") the properties of their bulk ingredient materials. This statement is especially true for chiral metamaterials, as unlocking certain degrees of freedom necessarily requires broken centrosymmetry. While the field of chiral electromagnetic/optical metamaterials has become rather mature, the field of elastic/mechanical metamaterials is just emerging and wide open. This research news reviews recent theoretical and experimental progress concerning 3D chiral mechanical and optical metamaterials, with special emphasis on work performed at KIT.
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Affiliation(s)
- I Fernandez-Corbaton
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - C Rockstuhl
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
- Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - P Ziemke
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - P Gumbsch
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
- Institute for Applied Materials, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
- Fraunhofer IWM, Wöhlerstr. 11, 79108, Freiburg, Germany
| | - A Albiez
- Institute for Applied Materials, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - R Schwaiger
- Institute for Applied Materials, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - T Frenzel
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
| | - M Kadic
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
- Institut FEMTO-ST, UMR 6174, CNRS, Université de Bourgogne Franche-Comté, 25000, Besançon, France
| | - M Wegener
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), 76128, Karlsruhe, Germany
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22
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Guo Q, You O, Yang B, Sellman JB, Blythe E, Liu H, Xiang Y, Li J, Fan D, Chen J, Chan CT, Zhang S. Observation of Three-Dimensional Photonic Dirac Points and Spin-Polarized Surface Arcs. PHYSICAL REVIEW LETTERS 2019; 122:203903. [PMID: 31172768 DOI: 10.1103/physrevlett.122.203903] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 05/28/2023]
Abstract
Three-dimensional (3D) Dirac points inheriting relativistic effects from high-energy physics appear as gapless excitations in the topological band theory. Hosting fourfold linear dispersion, they play the central role among various topological phases, such as representing the degeneracy of paired Weyl nodes carrying opposite chiralities. While they have been extensively investigated in solid state systems for electrons, 3D Dirac points have not yet been observed in any classical systems. Here, we experimentally demonstrate 3D photonic Dirac points in the microwave region with an elaborately designed metamaterial, where two symmetrically placed Dirac points are stabilized by electromagnetic duality symmetry. Furthermore, spin-polarized surface arcs (counterparts of Fermi arcs in electronic systems) are demonstrated, which opens the gate toward implementing spin-multiplexed topological surface wave propagation. Closely linked to other exotic states through topological phase transitions, our system offers an effective medium platform for topological photonics.
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Affiliation(s)
- Qinghua Guo
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
- Department of Physics and Center for Metamaterials Research, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Oubo You
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
- International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education, Shenzhen University, Shenzhen 518060, China
| | - Biao Yang
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
| | - James B Sellman
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
| | - Edward Blythe
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
| | - Hongchao Liu
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
| | - Yuanjiang Xiang
- International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education, Shenzhen University, Shenzhen 518060, China
| | - Jensen Li
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
- Department of Physics and Center for Metamaterials Research, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Dianyuan Fan
- International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education, Shenzhen University, Shenzhen 518060, China
| | - Jing Chen
- School of Physics, Nankai University, Tianjin 300071, China
| | - C T Chan
- Department of Physics and Center for Metamaterials Research, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Shuang Zhang
- School of Physics & Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom
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23
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Abstract
We consider the helicity and chirality of the free electromagnetic field, and advocate the former as a means of characterising the interaction of chiral light with matter. This is in view of the intuitive quantum form of the helicity density operator, and of the dual symmetry transformation generated by its conservation. We go on to review the form of the helicity density and its associated continuity equation in free space, in the presence of local currents and charges, and upon interaction with bulk media, leading to characterisation of both microscopic and macroscopic sources of helicity.
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24
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Bliokh KY, Leykam D, Lein M, Nori F. Topological non-Hermitian origin of surface Maxwell waves. Nat Commun 2019; 10:580. [PMID: 30718477 PMCID: PMC6362114 DOI: 10.1038/s41467-019-08397-6] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 01/08/2019] [Indexed: 11/09/2022] Open
Abstract
Maxwell electromagnetism, describing the wave properties of light, was formulated 150 years ago. More than 60 years ago it was shown that interfaces between optical media (including dielectrics, metals, negative-index materials) can support surface electromagnetic waves, which now play crucial roles in plasmonics, metamaterials, and nano-photonics. Here we show that surface Maxwell waves at interfaces between homogeneous isotropic media described by real permittivities and permeabilities have a topological origin explained by the bulk-boundary correspondence. Importantly, the topological classification is determined by the helicity operator, which is generically non-Hermitian even in lossless optical media. The corresponding topological invariant, which determines the number of surface modes, is a \documentclass[12pt]{minimal}
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\begin{document}$${\Bbb Z}_4$$\end{document}Z4 number (or a pair of \documentclass[12pt]{minimal}
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\begin{document}$${\Bbb Z}_2$$\end{document}Z2 numbers) describing the winding of the complex helicity spectrum across the interface. Our theory provides a new twist and insights for several areas of wave physics: Maxwell electromagnetism, topological quantum states, non-Hermitian wave physics, and metamaterials. Electromagnetic surface waves, derived from Maxwell theory, underpin many optical effects and applications. Here, Bliokh et al. show that surface waves at interfaces between isotropic media have a topological origin described by the non-Hermitian helicity operator and bulk-boundary correspondence.
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Affiliation(s)
- Konstantin Y Bliokh
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama, 351-0198, Japan. .,Nonlinear Physics Centre, RSPE, The Australian National University, Canberra, ACT, 0200, Australia.
| | - Daniel Leykam
- Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea
| | - Max Lein
- Advanced Institute of Materials Research, Tohoku University, Sendai, 980-8577, Japan
| | - Franco Nori
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama, 351-0198, Japan.,Physics Department, University of Michigan, Ann Arbor, MI, 48109-1040, USA
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25
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Büse A, Juan ML, Tischler N, D'Ambrosio V, Sciarrino F, Marrucci L, Molina-Terriza G. Symmetry Protection of Photonic Entanglement in the Interaction with a Single Nanoaperture. PHYSICAL REVIEW LETTERS 2018; 121:173901. [PMID: 30411929 DOI: 10.1103/physrevlett.121.173901] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Indexed: 06/08/2023]
Abstract
In this work, we experimentally show that quantum entanglement can be symmetry protected in the interaction with a single subwavelength plasmonic nanoaperture, with a total volume of V∼0.2λ^{3}. In particular, we experimentally demonstrate that two-photon entanglement can be either completely preserved or completely lost after the interaction with the nanoaperture, solely depending on the relative phase between the quantum states. We achieve this effect by using specially engineered two-photon states to match the properties of the nanoaperture. In this way we can access a symmetry protected state, i.e., a state constrained by the geometry of the interaction to retain its entanglement. In spite of the small volume of interaction, we show that the symmetry protected entangled state retains its main properties. This connection between nanophotonics and quantum optics probes the fundamental limits of the phenomenon of quantum interference.
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Affiliation(s)
- Alexander Büse
- Department of Physics & Astronomy, Macquarie University, NSW 2109 Sydney, Australia
| | - Mathieu L Juan
- Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria
- Institute for Experimental Physics, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Nora Tischler
- Centre for Quantum Dynamics, Griffith University, Brisbane 4111, Australia
| | - Vincenzo D'Ambrosio
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, E-08860 Castelldefels, Barcelona, Spain
- Dipartimento di Fisica, Università di Napoli Federico II, 80126 Napoli, Italy
| | - Fabio Sciarrino
- Dipartimento di Fisica, Sapienza Università di Roma, I-00185 Roma, Italy
| | - Lorenzo Marrucci
- Dipartimento di Fisica, Università di Napoli Federico II, 80126 Napoli, Italy
| | - Gabriel Molina-Terriza
- Centro de Física de Materiales (MPC) and Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastin, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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26
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Revah M, Nechayev S, Gorodetski Y. Unusual polarizing effect of cylindrical plasmonic holes. OPTICS LETTERS 2018; 43:4374-4377. [PMID: 30211867 DOI: 10.1364/ol.43.004374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
We observe an unusual polarization state conversion in the light that passes through a cylindrical hole in a thick metal film. This phenomenon is related to the helicity locking of the guided mode due to the plasmonic transverse spin-an intrinsic angular momentum of the surface waves. We show how this effect is linked to the generation of the plasmonic vortex inside the hole and can be altered by varying the hole diameter. In addition, the total light transmission through the hole is shown to be partially contributed from the direct transmission, which can further modify the resulting light polarization state.
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27
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Gutsche P, Nieto-Vesperinas M. Optical Chirality of Time-Harmonic Wavefields for Classification of Scatterers. Sci Rep 2018; 8:9416. [PMID: 29925847 PMCID: PMC6010445 DOI: 10.1038/s41598-018-27496-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/01/2018] [Indexed: 11/08/2022] Open
Abstract
We derive expressions for the scattering, extinction and conversion of the chirality of monochromatic light scattered by bodies which are characterized by a T-matrix. In analogy to the conditions obtained from the conservation of energy, these quantities enable the classification of arbitrary scattering objects due to their full, i.e. either chiral or achiral, electromagnetic response. To this end, we put forward and determine the concepts of duality and breaking of duality symmetry, anti-duality, helicity variation, helicity annhiliation and the breaking of helicity annihilation. Different classes, such as chiral and dual scatterers, are illustrated in this analysis with model examples of spherical and non-spherical shape. As for spheres, these concepts are analysed by considering non-Rayleigh dipolar dielectric particles of high refractive index, which, having a strong magnetic response to the incident wavefield, offer an excellent laboratory to test and interpret such changes in the chirality of the illumination. In addition, comparisons with existing experimental data are made.
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Affiliation(s)
- Philipp Gutsche
- Freie Universität Berlin, Mathematics Institute, 14195 Berlin, Germany.
- Zuse Institute Berlin, Computational Nano Optics, 14195 Berlin, Germany.
| | - Manuel Nieto-Vesperinas
- Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Madrid, 28049, Spain
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28
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Alpeggiani F, Bliokh KY, Nori F, Kuipers L. Electromagnetic Helicity in Complex Media. PHYSICAL REVIEW LETTERS 2018; 120:243605. [PMID: 29956970 DOI: 10.1103/physrevlett.120.243605] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Indexed: 06/08/2023]
Abstract
Optical helicity density is usually discussed for monochromatic electromagnetic fields in free space. It plays an important role in the interaction with chiral molecules or nanoparticles. Here we introduce the optical helicity density in a dispersive isotropic medium. Our definition is consistent with biorthogonal Maxwell electromagnetism in optical media and the Brillouin energy density as well as with the recently introduced canonical momentum and spin of light in dispersive media. We consider a number of examples, including electromagnetic waves in dielectrics, negative-index materials, and metals, as well as interactions of light in a medium with chiral and magnetoelectric molecules.
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Affiliation(s)
- F Alpeggiani
- Department of Quantum Nanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
| | - K Y Bliokh
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama 351-0198, Japan
- Nonlinear Physics Centre, RSPE, The Australian National University, Canberra ACT 0200, Australia
| | - F Nori
- Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama 351-0198, Japan
- Physics Department, University of Michigan, Ann Arbor, Michigan 48109-1040, USA
| | - L Kuipers
- Department of Quantum Nanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
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29
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Guo Q, Yang B, Xia L, Gao W, Liu H, Chen J, Xiang Y, Zhang S. Three Dimensional Photonic Dirac Points in Metamaterials. PHYSICAL REVIEW LETTERS 2017; 119:213901. [PMID: 29219411 DOI: 10.1103/physrevlett.119.213901] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Topological semimetals, representing a new topological phase that lacks a full band gap in bulk states and exhibiting nontrivial topological orders, recently have been extended to photonic systems, predominantly in photonic crystals and to a lesser extent metamaterials. Photonic crystal realizations of Dirac degeneracies are protected by various space symmetries, where Bloch modes span the spin and orbital subspaces. Here, we theoretically show that Dirac points can also be realized in effective media through the intrinsic degrees of freedom in electromagnetism under electromagnetic duality. A pair of spin-polarized Fermi-arc-like surface states is observed at the interface between air and the Dirac metamaterials. Furthermore, eigenreflection fields show the decoupling process from a Dirac point to two Weyl points. We also find the topological correlation between a Dirac point and vortex or vector beams in classical photonics. The experimental feasibility of our scheme is demonstrated by designing a realistic metamaterial structure. The theoretical proposal of the photonic Dirac point lays the foundation for unveiling the connection between intrinsic physics and global topology in electromagnetism.
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Affiliation(s)
- Qinghua Guo
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Biao Yang
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Lingbo Xia
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
- Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Wenlong Gao
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hongchao Liu
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Jing Chen
- MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin 300071, China
| | - Yuanjiang Xiang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Shuang Zhang
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
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30
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Broadband suppression of backscattering at optical frequencies using low permittivity dielectric spheres. Sci Rep 2017; 7:14762. [PMID: 29116251 PMCID: PMC5677120 DOI: 10.1038/s41598-017-15192-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 10/20/2017] [Indexed: 11/08/2022] Open
Abstract
The exact suppression of backscattering from rotationally symmetric objects requires dual symmetric materials where ε r = μ r. This prevents their design at many frequency bands, including the optical one, because magnetic materials are not available. Electromagnetically small non-magnetic spheres of large permittivity offer an alternative. They can be tailored to exhibit balanced electric and magnetic dipole polarizabilities a 1 = b 1, which result in approximate zero backscattering. In this case, the effect is inherently narrowband. Here, we put forward a different alternative that allows broadband functionality: Wavelength-sized spheres made from low permittivity materials. The effect occurs in a parameter regime where approximate duality is met for all multipolar order a n ≈ b n , in a weakly wavelength dependence fashion. In addition, and despite of the low permittivity, the overall scattering response of these spheres is still significant. Scattering patterns are shown to be highly directive across an octave spanning band. The effect is analytically and numerically shown using the Mie coefficients.
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31
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Cameron RP, Götte JB, Barnett SM, Yao AM. Chirality and the angular momentum of light. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:20150433. [PMID: 28069764 PMCID: PMC5247477 DOI: 10.1098/rsta.2015.0433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/12/2016] [Indexed: 05/24/2023]
Abstract
Chirality is exhibited by objects that cannot be rotated into their mirror images. It is far from obvious that this has anything to do with the angular momentum of light, which owes its existence to rotational symmetries. There is nevertheless a subtle connection between chirality and the angular momentum of light. We demonstrate this connection and, in particular, its significance in the context of chiral light-matter interactions.This article is part of the themed issue 'Optical orbital angular momentum'.
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Affiliation(s)
- Robert P Cameron
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Jörg B Götte
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Stephen M Barnett
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Alison M Yao
- Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK
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32
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Nienhuis G. Analogies between optical and quantum mechanical angular momentum. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2015.0443. [PMID: 28069774 DOI: 10.1098/rsta.2015.0443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/13/2016] [Indexed: 05/24/2023]
Abstract
The insight that a beam of light can carry orbital angular momentum (AM) in its propagation direction came up in 1992 as a surprise. Nevertheless, the existence of momentum and AM of an electromagnetic field has been well known since the days of Maxwell. We compare the expressions for densities of AM in general three-dimensional modes and in paraxial modes. Despite their classical nature, these expressions have a suggestive quantum mechanical appearance, in terms of linear operators acting on mode functions. In addition, paraxial wave optics has several analogies with real quantum mechanics, both with the wave function of a free quantum particle and with a quantum harmonic oscillator. We discuss how these analogies can be applied.This article is part of the themed issue 'Optical orbital angular momentum'.
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Affiliation(s)
- Gerard Nienhuis
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, PO Box 9504, 2300 RA Leiden, The Netherlands
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33
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Garoli D, Zilio P, Gorodetski Y, Tantussi F, De Angelis F. Beaming of Helical Light from Plasmonic Vortices via Adiabatically Tapered Nanotip. NANO LETTERS 2016; 16:6636-6643. [PMID: 27618524 PMCID: PMC6660026 DOI: 10.1021/acs.nanolett.6b03359] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We demonstrate the generation of far-field propagating optical beams with a desired orbital angular momentum by using a smooth optical-mode transformation between a plasmonic vortex and free-space Laguerre-Gaussian modes. This is obtained by means of an adiabatically tapered gold tip surrounded by a spiral slit. The proposed physical model, backed up by the numerical study, brings about an optimized structure that is fabricated by using a highly reproducible secondary electron lithography technique. Optical measurements of the structure excellently agree with the theoretically predicted far-field distributions. This architecture provides a unique platform for a localized excitation of plasmonic vortices followed by its beaming.
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Affiliation(s)
- Denis Garoli
- Istituto
Italiano di Tecnologia, via Morego 30, I-16163 Genova, Italy
| | | | - Yuri Gorodetski
- Mechanical
Engineering Department and Electrical Engineering Department, Ariel University, Ariel, 40700 Israel
- E-mail:
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34
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Zambrana-Puyalto X, Bonod N. Tailoring the chirality of light emission with spherical Si-based antennas. NANOSCALE 2016; 8:10441-10452. [PMID: 27141982 DOI: 10.1039/c6nr00676k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Chirality of light is of fundamental importance in several enabling technologies with growing applications in life sciences, chemistry and photodetection. Recently, some attention has been focused on chiral quantum emitters. Consequently, optical antennas which are able to tailor the chirality of light emission are needed. Spherical nanoresonators such as colloids are of particular interest to design optical antennas since they can be synthesized at a large scale and they exhibit good optical properties. Here, we show that these colloids can be used to tailor the chirality of a chiral emitter. To this purpose, we derive an analytic formalism to model the interaction between a chiral emitter and a spherical resonator. We then compare the performances of metallic and dielectric spherical antennas to tailor the chirality of light emission. It is seen that, due to their strong electric dipolar response, metallic spherical nanoparticles spoil the chirality of light emission by yielding achiral fields. In contrast, thanks to the combined excitation of electric and magnetic modes, dielectric Si-based particles feature the ability to inhibit or to boost the chirality of light emission. Finally, it is shown that dual modes in dielectric antennas preserve the chirality of light emission.
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Affiliation(s)
- Xavier Zambrana-Puyalto
- Aix-Marseille Université, CNRS, Centrale Marseille, Institut Fresnel UMR 7249, 13013 Marseille, France.
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35
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Ren H, Li X, Zhang Q, Gu M. On-chip noninterference angular momentum multiplexing of broadband light. Science 2016; 352:805-9. [PMID: 27056843 DOI: 10.1126/science.aaf1112] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/09/2016] [Indexed: 01/29/2023]
Abstract
Angular momentum division has emerged as a physically orthogonal multiplexing method in high-capacity optical information technologies. However, the typical bulky elements used for information retrieval from the overall diffracted field, based on the interference method, impose a fundamental limit toward realizing on-chip multiplexing. We demonstrate noninterference angular momentum multiplexing by using a mode-sorting nanoring aperture with a chip-scale footprint as small as 4.2 micrometers by 4.2 micrometers, where nanoring slits exhibit a distinctive outcoupling efficiency on tightly confined plasmonic modes. The nonresonant mode-sorting sensitivity and scalability of our approach enable on-chip parallel multiplexing over a bandwidth of 150 nanometers in the visible wavelength range. The results offer the possibility of ultrahigh-capacity and miniaturized nanophotonic devices harnessing angular momentum division.
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Affiliation(s)
- Haoran Ren
- Centre for Micro-Photonics and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Xiangping Li
- Centre for Micro-Photonics and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. Institute of Photonics Technology, Jinan University, Guangzhou, China
| | - Qiming Zhang
- Centre for Micro-Photonics and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. Artificial Intelligence Nanophotonics Laboratory, School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Min Gu
- Centre for Micro-Photonics and Centre for Ultrahigh Bandwidth Devices for Optical Systems (CUDOS), Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia. Artificial Intelligence Nanophotonics Laboratory, School of Science, RMIT University, Melbourne, Victoria 3001, Australia.
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36
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Far-field measurements of vortex beams interacting with nanoholes. Sci Rep 2016; 6:22185. [PMID: 26911547 PMCID: PMC4766500 DOI: 10.1038/srep22185] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/03/2016] [Indexed: 12/02/2022] Open
Abstract
We measure the far-field intensity of vortex beams going through nanoholes. The process is analyzed in terms of helicity and total angular momentum. It is seen that the total angular momentum is preserved in the process, and helicity is not. We compute the ratio between the two transmitted helicity components, γm,p. We observe that this ratio is highly dependent on the helicity (p) and the angular momentum (m) of the incident vortex beam in consideration. Due to the mirror symmetry of the nanoholes, we are able to relate the transmission properties of vortex beams with a certain helicity and angular momentum, with the ones with opposite helicity and angular momentum. Interestingly, vortex beams enhance the γm,p ratio as compared to those obtained by Gaussian beams.
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37
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Fernandez-Corbaton I, Nanz S, Alaee R, Rockstuhl C. Exact dipolar moments of a localized electric current distribution. OPTICS EXPRESS 2015; 23:33044-33064. [PMID: 26831974 DOI: 10.1364/oe.23.033044] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The multipolar decomposition of current distributions is used in many branches of physics. Here, we obtain new exact expressions for the dipolar moments of a localized electric current distribution. The typical integrals for the dipole moments of electromagnetically small sources are recovered as the lowest order terms of the new expressions in a series expansion with respect to the size of the source. All the higher order terms can be easily obtained. We also provide exact and approximated expressions for dipoles that radiate a definite polarization handedness (helicity). Formally, the new exact expressions are only marginally more complex than their lowest order approximations.
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38
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Abstract
Maxwell's equations, formulated 150 years ago, ultimately describe properties of light, from classical electromagnetism to quantum and relativistic aspects. The latter ones result in remarkable geometric and topological phenomena related to the spin-1 massless nature of photons. By analyzing fundamental spin properties of Maxwell waves, we show that free-space light exhibits an intrinsic quantum spin Hall effect—surface modes with strong spin-momentum locking. These modes are evanescent waves that form, for example, surface plasmon-polaritons at vacuum-metal interfaces. Our findings illuminate the unusual transverse spin in evanescent waves and explain recent experiments that have demonstrated the transverse spin-direction locking in the excitation of surface optical modes. This deepens our understanding of Maxwell's theory, reveals analogies with topological insulators for electrons, and offers applications for robust spin-directional optical interfaces.
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Affiliation(s)
- Konstantin Y Bliokh
- Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198, Japan. Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia.
| | - Daria Smirnova
- Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia
| | - Franco Nori
- Center for Emergent Matter Science, RIKEN, Wako-shi, Saitama 351-0198, Japan. Department of Physics, University of Michigan, Ann Arbor, MI 48109-1040, USA.
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39
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Schmidt MK, Aizpurua J, Zambrana-Puyalto X, Vidal X, Molina-Terriza G, Sáenz JJ. Isotropically polarized speckle patterns. PHYSICAL REVIEW LETTERS 2015; 114:113902. [PMID: 25839272 DOI: 10.1103/physrevlett.114.113902] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Indexed: 06/04/2023]
Abstract
The polarization of the light scattered by an optically dense and random solution of dielectric nanoparticles shows peculiar properties when the scatterers exhibit strong electric and magnetic polarizabilities. While the distribution of the scattering intensity in these systems shows the typical irregular speckle patterns, the helicity of the incident light can be fully conserved when the electric and magnetic polarizabilities of the scatterers are equal. We show that the multiple scattering of helical beams by a random dispersion of "dual" dipolar nanospheres leads to a speckle pattern exhibiting a perfect isotropic constant polarization, a situation that could be useful in coherent control of light as well as in lasing in random media.
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Affiliation(s)
- Mikolaj K Schmidt
- Materials Physics Center CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 Donostia-San Sebastián, Spain
- Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain
| | - Javier Aizpurua
- Materials Physics Center CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, 20018 Donostia-San Sebastián, Spain
- Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain
| | - Xavier Zambrana-Puyalto
- Department of Physics and Astronomy, Macquarie University, North Ryde, New South Wales 2109, Australia
- ARC Center for Engineered Quantum Systems, Macquarie University, North Ryde, New South Wales 2109, Australia
| | - Xavier Vidal
- Department of Physics and Astronomy, Macquarie University, North Ryde, New South Wales 2109, Australia
| | - Gabriel Molina-Terriza
- Department of Physics and Astronomy, Macquarie University, North Ryde, New South Wales 2109, Australia
- ARC Center for Engineered Quantum Systems, Macquarie University, North Ryde, New South Wales 2109, Australia
| | - Juan José Sáenz
- Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain
- Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
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40
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Angular momentum-induced circular dichroism in non-chiral nanostructures. Nat Commun 2014; 5:4922. [DOI: 10.1038/ncomms5922] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 08/06/2014] [Indexed: 11/08/2022] Open
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41
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Bliokh KY, Kivshar YS, Nori F. Magnetoelectric effects in local light-matter interactions. PHYSICAL REVIEW LETTERS 2014; 113:033601. [PMID: 25083644 DOI: 10.1103/physrevlett.113.033601] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Indexed: 06/03/2023]
Abstract
We study the generic dipole interaction of a monochromatic free-space electromagnetic field with a bi-isotropic nanoparticle or a molecule. Contributions associated with the breaking of dual, P, and T symmetries are responsible for electric-magnetic asymmetry, chirality, and the nonreciprocal magnetoelectric effect, respectively. We calculate absorption rates, radiation forces, and radiation torques for the nanoparticle and introduce novel field characteristics quantifying the transfer of energy, momentum, and angular momentum due to the three symmetry-breaking effects. In particular, we put forward a concept of "magnetoelectric energy density," quantifying the local PT symmetry of the field. Akin to the "superchiral" light suggested recently for local probing of molecular chirality, here we suggest employing complex fields for a sensitive probing of the nonreciprocal magnetoelectric effect in nanoparticles or molecules.
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Affiliation(s)
- Konstantin Y Bliokh
- iTHES Research Group, RIKEN, Wako-shi, Saitama 351-0198, Japan and CEMS, RIKEN, Wako-shi, Saitama 351-0198, Japan
| | - Yuri S Kivshar
- Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200, Australia
| | - Franco Nori
- CEMS, RIKEN, Wako-shi, Saitama 351-0198, Japan and Physics Department, University of Michigan, Ann Arbor, Michigan 48109-1040, USA
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42
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Fernandez-Corbaton I. Forward and backward helicity scattering coefficients for systems with discrete rotational symmetry. OPTICS EXPRESS 2013; 21:29885-29893. [PMID: 24514539 DOI: 10.1364/oe.21.029885] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The forward and backward scattering off linear systems with discrete rotational symmetries R(z)(2π/n) with n ≥ 3 are shown to be restricted by symmetry reasons. Along the symmetry axis, forward scattering can only be helicity preserving and backward scattering can only be helicity flipping. These restrictions do not exist for n < 3. If, in addition to the n ≥ 3 discrete rotational symmetry, the system has duality symmetry (obeys the helicity conservation law), it will exhibit zero backscattering. The results pinpoint the underlying symmetry reasons for some notable scattering properties of R(z)(2π/4) symmetric systems that have been reported in the metamaterials and radar literature. Applications to planar metamaterials and solar cells are briefly discussed.
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