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Meng F, Cao L, Mangeney J, Roskos HG. Strong coupling of metamaterials with cavity photons: toward non-Hermitian optics. NANOPHOTONICS 2024; 13:2443-2451. [PMID: 38836105 PMCID: PMC11147495 DOI: 10.1515/nanoph-2023-0899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/23/2024] [Indexed: 06/06/2024]
Abstract
The investigation of strong coupling between light and matter is an important field of research. Its significance arises not only from the emergence of a plethora of intriguing chemical and physical phenomena, often novel and unexpected, but also from its provision of important tool sets for the design of core components for novel chemical, electronic, and photonic devices such as quantum computers, lasers, amplifiers, modulators, sensors and more. Strong coupling has been demonstrated for various material systems and spectral regimes, each exhibiting unique features and applications. In this perspective, we will focus on a sub-field of this domain of research and discuss the strong coupling between metamaterials and photonic cavities at THz frequencies. The metamaterials, themselves electromagnetic resonators, serve as "artificial atoms". We provide a concise overview of recent advances and outline possible research directions in this vital and impactful field of interdisciplinary science.
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Affiliation(s)
- Fanqi Meng
- Physikalisches Institut, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
| | - Lei Cao
- Physikalisches Institut, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
- State Key Laboratory of Advanced Electromagnetic Technology, Huazhong University of Science and Technology, Wuhan430074, China
| | | | - Hartmut G. Roskos
- Physikalisches Institut, Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
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2
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Chernyadiev AV, But DB, Ivonyak Y, Ikamas K, Lisauskas A. A CMOS-integrated terahertz near-field sensor based on an ultra-strongly coupled meta-atom. Sci Rep 2024; 14:11483. [PMID: 38769178 PMCID: PMC11106299 DOI: 10.1038/s41598-024-61971-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 05/13/2024] [Indexed: 05/22/2024] Open
Abstract
Recently, plasmonic-based sensors operating in the terahertz frequency range have emerged as perspective tools for rapid and efficient label-free biosensing applications. In this work, we present a fully electronic approach allowing us to achieve state-of-the-art sensitivity by utilizing a near-field-coupled electronic sensor. We demonstrate that the proposed concept enables the efficient implementation and probing of a so-called ultra-strongly coupled sub-wavelength meta-atom as well as a single resonant circuit, allowing to limit the volume of material under test down to a few picoliter range. The sensor has been monolithically integrated into a cost-efficient silicon-based CMOS technology. Our findings are supported by both numerical and analytical models and validated through experiments. They lay the groundwork for near-future developments, outlining the perspectives for a terahertz microfluidic lab-on-chip dielectric spectroscopy sensor.
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Affiliation(s)
- Alexander V Chernyadiev
- CENTERA Laboratories, Institute of High Pressure Physics PAS, Sokołowska st. 29/37, 01-142, Warsaw, Poland.
| | - Dmytro B But
- CENTERA Laboratories, Institute of High Pressure Physics PAS, Sokołowska st. 29/37, 01-142, Warsaw, Poland
| | - Yurii Ivonyak
- CENTERA Laboratories, Institute of High Pressure Physics PAS, Sokołowska st. 29/37, 01-142, Warsaw, Poland
| | - Kęstutis Ikamas
- Institute of Applied Electrodynamics and Telecommunications, Vilnius University, Saulėtekio av. 9, 10222, Vilnius, Lithuania
| | - Alvydas Lisauskas
- Institute of Applied Electrodynamics and Telecommunications, Vilnius University, Saulėtekio av. 9, 10222, Vilnius, Lithuania.
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3
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Todorov Y, Dhillon S, Mangeney J. THz quantum gap: exploring potential approaches for generating and detecting non-classical states of THz light. NANOPHOTONICS 2024; 13:1681-1691. [PMID: 38681681 PMCID: PMC11052537 DOI: 10.1515/nanoph-2023-0757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/30/2023] [Indexed: 05/01/2024]
Abstract
Over the past few decades, THz technology has made considerable progress, evidenced by the performance of current THz sources and detectors, as well as the emergence of several THz applications. However, in the realm of quantum technologies, the THz spectral domain is still in its infancy, unlike neighboring spectral domains that have flourished in recent years. Notably, in the microwave domain, superconducting qubits currently serve as the core of quantum computers, while quantum cryptography protocols have been successfully demonstrated in the visible and telecommunications domains through satellite links. The THz domain has lagged behind in these impressive advancements. Today, the current gap in the THz domain clearly concerns quantum technologies. Nonetheless, the emergence of quantum technologies operating at THz frequencies will potentially have a significant impact. Indeed, THz radiation holds significant promise for wireless communications with ultimate security owing to its low sensitivity to atmospheric disturbances. Moreover, it has the potential to raise the operating temperature of solid-state qubits, effectively addressing existing scalability issues. In addition, THz radiation can manipulate the quantum states of molecules, which are recognized as new platforms for quantum computation and simulation with long range interactions. Finally, its ability to penetrate generally opaque materials or its resistance to Rayleigh scattering are very appealing features for quantum sensing. In this perspective, we will discuss potential approaches that offer exciting prospects for generating and detecting non-classical states of THz light, thereby opening doors to significant breakthroughs in THz quantum technologies.
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Affiliation(s)
- Yanko Todorov
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Sukhdeep Dhillon
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Juliette Mangeney
- Laboratoire de Physique de l’Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
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4
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Mornhinweg J, Diebel L, Halbhuber M, Riepl J, Cortese E, De Liberato S, Bougeard D, Huber R, Lange C. Sculpting ultrastrong light-matter coupling through spatial matter structuring. NANOPHOTONICS 2024; 13:1909-1915. [PMID: 38681678 PMCID: PMC11052535 DOI: 10.1515/nanoph-2023-0604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 12/10/2023] [Indexed: 05/01/2024]
Abstract
The central theme of cavity quantum electrodynamics is the coupling of a single optical mode with a single matter excitation, leading to a doublet of cavity polaritons which govern the optical properties of the coupled structure. Especially in the ultrastrong coupling regime, where the ratio of the vacuum Rabi frequency and the quasi-resonant carrier frequency of light, ΩR/ω c, approaches unity, the polariton doublet bridges a large spectral bandwidth 2ΩR, and further interactions with off-resonant light and matter modes may occur. The resulting multi-mode coupling has recently attracted attention owing to the additional degrees of freedom for designing light-matter coupled resonances, despite added complexity. Here, we experimentally implement a novel strategy to sculpt ultrastrong multi-mode coupling by tailoring the spatial overlap of multiple modes of planar metallic THz resonators and the cyclotron resonances of Landau-quantized two-dimensional electrons, on subwavelength scales. We show that similarly to the selection rules of classical optics, this allows us to suppress or enhance certain coupling pathways and to control the number of light-matter coupled modes, their octave-spanning frequency spectra, and their response to magnetic tuning. This offers novel pathways for controlling dissipation, tailoring quantum light sources, nonlinearities, correlations as well as entanglement in quantum information processing.
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Affiliation(s)
- Joshua Mornhinweg
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
- Department of Physics, TU Dortmund University, 44227Dortmund, Germany
| | - Laura Diebel
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
| | - Maike Halbhuber
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
| | - Josef Riepl
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
| | - Erika Cortese
- School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK
| | - Simone De Liberato
- School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ, UK
- IFN – Istituto di Fotonica e Nanotecnologie, CNR, I-20133Milan, Italy
| | - Dominique Bougeard
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
| | - Rupert Huber
- Department of Physics, University of Regensburg, 93040Regensburg, Germany
| | - Christoph Lange
- Department of Physics, TU Dortmund University, 44227Dortmund, Germany
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5
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Kuroyama K, Kwoen J, Arakawa Y, Hirakawa K. Coherent Interaction of a Few-Electron Quantum Dot with a Terahertz Optical Resonator. PHYSICAL REVIEW LETTERS 2024; 132:066901. [PMID: 38394566 DOI: 10.1103/physrevlett.132.066901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/07/2023] [Accepted: 12/06/2023] [Indexed: 02/25/2024]
Abstract
We have investigated light-matter hybrid excitations in a quantum dot (QD) THz resonator coupled system. We fabricate a gate-defined QD near a THz split-ring resonator (SRR) by using a AlGaAs/GaAs two-dimensional electron system. By illuminating the system with THz radiation, the QD shows a current change whose spectrum exhibits coherent coupling between the electrons in the QD and the SRR as well as coupling between the two-dimensional electron system and the SRR. The latter coupling enters the ultrastrong coupling regime and the electron excitation in the QD also exhibits coherent coupling with the SRR with the remarkably large coupling constant, despite the fact that only a few electrons reside in the QD.
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Affiliation(s)
- Kazuyuki Kuroyama
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Jinkwan Kwoen
- Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Yasuhiko Arakawa
- Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Kazuhiko Hirakawa
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
- Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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6
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Langevin D, Verlhac C, Jaeck J, Abou-Hamdan L, Taupeau E, Fix B, Bardou N, Dupuis C, De Wilde Y, Haïdar R, Bouchon P. Experimental Investigation of the Thermal Emission Cross Section of Nanoresonators Using Hierarchical Poisson-Disk Distributions. PHYSICAL REVIEW LETTERS 2024; 132:043801. [PMID: 38335346 DOI: 10.1103/physrevlett.132.043801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 12/08/2023] [Indexed: 02/12/2024]
Abstract
Effective cross sections of nano-objects are fundamental properties that determine their ability to interact with light. However, measuring them for individual resonators directly and quantitatively remains challenging, particularly because of the very low signals involved. Here, we experimentally measure the thermal emission cross section of metal-insulator-metal nanoresonators using a stealthy hyperuniform distribution based on a hierarchical Poisson-disk algorithm. In such distributions, there are no long-range interactions between antennas, and we show that the light emitted by such metasurfaces behaves as the sum of cross sections of independent nanoantennas, enabling direct retrieval of the single resonator contribution. The emission cross section at resonance is found to be on the order of λ_{0}^{2}/3, a value that is nearly 3 times larger than the theoretical maximal absorption cross section of a single particle, but remains smaller than the maximal extinction cross section. This measurement technique can be generalized to any single resonator cross section, and we also apply it to a lossy dielectric layer.
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Affiliation(s)
- Denis Langevin
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | - Clément Verlhac
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | - Julien Jaeck
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | | | - Eva Taupeau
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | - Baptiste Fix
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | - Nathalie Bardou
- Center for Nanosciences and Nanotechnology (C2N) - CNRS, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120 Palaiseau, France
| | - Christophe Dupuis
- Center for Nanosciences and Nanotechnology (C2N) - CNRS, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120 Palaiseau, France
| | - Yannick De Wilde
- Institut Langevin, ESPCI Paris, PSL University, CNRS, 1 rue Jussieu, F-75005 Paris, France
| | - Riad Haïdar
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
| | - Patrick Bouchon
- DOTA, ONERA, Université Paris-Saclay, F-91123 Palaiseau, France
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Kuroyama K, Kwoen J, Arakawa Y, Hirakawa K. Electrical Detection of Ultrastrong Coherent Interaction between Terahertz Fields and Electrons Using Quantum Point Contacts. NANO LETTERS 2023; 23:11402-11408. [PMID: 37910773 DOI: 10.1021/acs.nanolett.3c02272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Light-matter interaction in the ultrastrong coupling regime is attracting considerable attention owing to its applications to coherent control of material properties by a vacuum fluctuation field. However, electrical access to such an ultrastrongly coupled system is very challenging. In this work, we have fabricated a gate-defined quantum point contact (QPC) near the gap of a terahertz (THz) split-ring resonator (SRR) fabricated on a GaAs two-dimensional (2D) electron system. By illuminating the system with external THz radiation, the QPC shows a photocurrent spectrum which exhibits significant anticrossing that arises from coupling between the cyclotron resonance of the 2D electrons and the SRR. The observed photocurrent signal can be explained by energy-selective transmission/reflection of the quantum Hall edge channels at the QPC. Furthermore, at the same gate voltage and magnetic field conditions under which the anticrossing signal was observed, the QPC exhibits anomalous conductance modulation even in the dark environment.
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Affiliation(s)
- Kazuyuki Kuroyama
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Jinkwan Kwoen
- Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Yasuhiko Arakawa
- Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Kazuhiko Hirakawa
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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8
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Ashida Y, İmamoğlu A, Demler E. Cavity Quantum Electrodynamics with Hyperbolic van der Waals Materials. PHYSICAL REVIEW LETTERS 2023; 130:216901. [PMID: 37295119 DOI: 10.1103/physrevlett.130.216901] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/27/2023] [Accepted: 05/04/2023] [Indexed: 06/12/2023]
Abstract
The ground-state properties and excitation energies of a quantum emitter can be modified in the ultrastrong coupling regime of cavity quantum electrodynamics (QED) where the light-matter interaction strength becomes comparable to the cavity resonance frequency. Recent studies have started to explore the possibility of controlling an electronic material by embedding it in a cavity that confines electromagnetic fields in deep subwavelength scales. Currently, there is a strong interest in realizing ultrastrong-coupling cavity QED in the terahertz (THz) part of the spectrum, since most of the elementary excitations of quantum materials are in this frequency range. We propose and discuss a promising platform to achieve this goal based on a two-dimensional electronic material encapsulated by a planar cavity consisting of ultrathin polar van der Waals crystals. As a concrete setup, we show that nanometer-thick hexagonal boron nitride layers should allow one to reach the ultrastrong coupling regime for single-electron cyclotron resonance in a bilayer graphene. The proposed cavity platform can be realized by a wide variety of thin dielectric materials with hyperbolic dispersions. Consequently, van der Waals heterostructures hold the promise of becoming a versatile playground for exploring the ultrastrong-coupling physics of cavity QED materials.
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Affiliation(s)
- Yuto Ashida
- Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Institute for Physics of Intelligence, University of Tokyo, 7-3-1 Hongo, Tokyo 113-0033, Japan
| | - Ataç İmamoğlu
- Institute of Quantum Electronics, ETH Zurich, CH-8093 Zürich, Switzerland
| | - Eugene Demler
- Institute for Theoretical Physics, ETH Zurich, 8093 Zürich, Switzerland
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Malerba M, Sotgiu S, Schirato A, Baldassarre L, Gillibert R, Giliberti V, Jeannin M, Manceau JM, Li L, Davies AG, Linfield EH, Alabastri A, Ortolani M, Colombelli R. Detection of Strong Light-Matter Interaction in a Single Nanocavity with a Thermal Transducer. ACS NANO 2022; 16:20141-20150. [PMID: 36399696 DOI: 10.1021/acsnano.2c04452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The concept of strong light-matter coupling has been demonstrated in semiconductor structures, and it is poised to revolutionize the design and implementation of components, including solid state lasers and detectors. We demonstrate an original nanospectroscopy technique that permits the study of the light-matter interaction in single subwavelength-sized nanocavities where far-field spectroscopy is not possible using conventional techniques. We inserted a thin (∼150 nm) polymer layer with negligible absorption in the mid-infrared range (5 μm < λ < 12 μm) inside a metal-insulator-metal resonant cavity, where a photonic mode and the intersubband transition of a semiconductor quantum well are strongly coupled. The intersubband transition peaks at λ = 8.3 μm, and the nanocavity is overall 270 nm thick. Acting as a nonperturbative transducer, the polymer layer introduces only a limited alteration of the optical response while allowing to reveal the optical power absorbed inside the concealed cavity. Spectroscopy of the cavity losses is enabled by the polymer thermal expansion due to heat dissipation in the active part of the cavity, and performed using atomic force microscopy (AFM). This innovative approach allows the typical anticrossing characteristic of the polaritonic dispersion to be identified in the cavity loss spectra at the single nanoresonator level. Results also suggest that near-field coupling of the external drive field to the top metal patch mediated by a metal-coated AFM probe tip is possible, and it enables the near-field mapping of the cavity mode symmetry including in the presence of a strong light-matter interaction.
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Affiliation(s)
- Mario Malerba
- Centre de Nanosciences et de Nanotechnologies (C2N), CNRS UMR 9001, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120Palaiseau, France
| | - Simone Sotgiu
- Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185Rome, Italy
| | - Andrea Schirato
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133Milan, Italy
- Istituto Italiano di Tecnologia, via Morego 30, 16163Genoa, Italy
| | - Leonetta Baldassarre
- Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185Rome, Italy
| | - Raymond Gillibert
- Center for Life NanoScience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161Rome, Italy
| | - Valeria Giliberti
- Center for Life NanoScience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161Rome, Italy
| | - Mathieu Jeannin
- Centre de Nanosciences et de Nanotechnologies (C2N), CNRS UMR 9001, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120Palaiseau, France
| | - Jean-Michel Manceau
- Centre de Nanosciences et de Nanotechnologies (C2N), CNRS UMR 9001, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120Palaiseau, France
| | - Lianhe Li
- School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, LS29JTLeeds, United Kingdom
| | - Alexander Giles Davies
- School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, LS29JTLeeds, United Kingdom
| | - Edmund H Linfield
- School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, LS29JTLeeds, United Kingdom
| | - Alessandro Alabastri
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas77005, United States
| | - Michele Ortolani
- Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185Rome, Italy
- Center for Life NanoScience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161Rome, Italy
| | - Raffaele Colombelli
- Centre de Nanosciences et de Nanotechnologies (C2N), CNRS UMR 9001, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120Palaiseau, France
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Scalari G, Rajabali S, Jöchl E, Markmann S, de Liberato S, Cortese E, Beck M, Faist J. Non-locality and single meta-atom spectroscopy in THz Landau polaritons. EPJ WEB OF CONFERENCES 2022. [DOI: 10.1051/epjconf/202226608013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We will discuss, theoretically and experimentally, the existence of a limit to the possibility of arbitrarily increasing electromagnetic confinement in polaritonic systems, where strongly sub-wavelength fields can excite a continuum of high-momenta propagative magnetoplasmons. This leads to peculiar nonlocal polaritonic effects, as certain polaritonic features disappear and the system enters in the regime of discrete-to-continuum strong coupling. We will as well present experiments reporting spectroscopy of a single, ultrastrongly coupled, highly subwavelength resonator operating at 300 GHz.
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