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Alexey Y Nikitin - One of the best experts on this subject based on the ideXlab platform.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Saul Velez, Christopher Tollan, Zhigao DaiAbstract:Polaritons-hybrid light-matter excitations-enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3-5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light-matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Shaojuan Li, Peining Li, Saul VelezAbstract:Polaritons—hybrid light–matter excitations—enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3–5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light–matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics. Observation of the anisotropic propagation of Polaritons along the surface of layered, semiconducting α-MoO3 confirms the existence of this phenomenon in natural materials.
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Boron nitride nanoresonators for phonon-enhanced molecular vibrational spectroscopy at the strong coupling limit
Light: Science & Applications, 2018Co-Authors: Marta Autore, Irene Dolado, Francisco J Alfaro-mozaz, Ruben Esteban, Ainhoa Atxabal, Fèlix Casanova, Luis E Hueso, Pablo Alonso-gonzález, Javier Aizpurua, Alexey Y NikitinAbstract:Infrared spectroscopy is a powerful tool for characterizing materials based on their specific vibrational fingerprints. However, its ability to characterize small amounts or thin layers of molecules is limited by their extremely small infrared absorption cross-sections. This limitation can be overcome by surface-enhanced infrared absorption spectroscopy (SEIRA), which exploits the field enhancement provided by plasmon Polaritons on thin metal films or resonant metallic nanostructures. Now, Rainer Hillenbrand from CIC nanoGUNE in San Sebastián (Spain) and co-workers have developed highly sensitive phonon-Polariton resonators for SEIRA detection, based on hexagonal boron nitride ribbons, which exhibit quality factors much higher than their plasmonic counterparts. They demonstrated phonon-enhanced molecular vibrational spectroscopy with sensitivity down to femtomolar levels, approaching the strong coupling limit. Enhanced light-matter interactions are the basis of surface-enhanced infrared absorption (SEIRA) spectroscopy, and conventionally rely on plasmonic materials and their capability to focus light to nanoscale spot sizes. Phonon Polariton nanoresonators made of polar crystals could represent an interesting alternative, since they exhibit large quality factors, which go far beyond those of their plasmonic counterparts. The recent emergence of van der Waals crystals enables the fabrication of high-quality nanophotonic resonators based on phonon Polaritons, as reported for the prototypical infrared-phononic material hexagonal boron nitride (h-BN). In this work we use, for the first time, phonon-Polariton-resonant h-BN ribbons for SEIRA spectroscopy of small amounts of organic molecules in Fourier transform infrared spectroscopy. Strikingly, the interaction between phonon Polaritons and molecular vibrations reaches experimentally the onset of the strong coupling regime, while numerical simulations predict that vibrational strong coupling can be fully achieved. Phonon Polariton nanoresonators thus could become a viable platform for sensing, local control of chemical reactivity and infrared quantum cavity optics experiments.
Pablo Alonsogonzalez - One of the best experts on this subject based on the ideXlab platform.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Saul Velez, Christopher Tollan, Zhigao DaiAbstract:Polaritons-hybrid light-matter excitations-enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3-5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light-matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Shaojuan Li, Peining Li, Saul VelezAbstract:Polaritons—hybrid light–matter excitations—enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3–5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light–matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics. Observation of the anisotropic propagation of Polaritons along the surface of layered, semiconducting α-MoO3 confirms the existence of this phenomenon in natural materials.
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boron nitride nanoresonators for phonon enhanced molecular vibrational spectroscopy at the strong coupling limit
arXiv: Optics, 2018Co-Authors: Marta Autore, Pablo Alonsogonzalez, Irene Dolado, Ruben Esteban, Ainhoa Atxabal, Fèlix Casanova, Luis E Hueso, Javier Aizpurua, Francisco Javier AlfaromozazAbstract:Enhanced light-matter interactions are the basis of surface enhanced infrared absorption (SEIRA) spectroscopy, and conventionally rely on plasmonic materials and their capability to focus light to nanoscale spot sizes. Phonon Polariton nanoresonators made of polar crystals could represent an interesting alternative, since they exhibit large quality factors, which go far beyond those of their plasmonic counterparts. The recent emergence of van der Waals crystals enables the fabrication of high-quality nanophotonic resonators based on phonon Polaritons, as reported for the prototypical infrared-phononic material hexagonal boron nitride (h-BN). In this work we use, for the first time, phonon-Polariton-resonant h-BN ribbons for SEIRA spectroscopy of small amounts of organic molecules in Fourier transform infrared spectroscopy. Strikingly, the interaction between phonon Polaritons and molecular vibrations reaches experimentally the onset of the strong coupling regime, while numerical simulations predict that vibrational strong coupling can be fully achieved. Phonon Polariton nanoresonators thus could become a viable platform for sensing, local control of chemical reactivity and infrared quantum cavity optics experiments.
Yoshihisa Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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exciton Polariton condensates
Nature Physics, 2014Co-Authors: Tim Byrnes, Na Young Kim, Yoshihisa YamamotoAbstract:Exciton–Polaritons, resulting from the light–matter coupling between an exciton and a photon in a cavity, form Bose–Einstein-like condensates above a critical density. Various aspects of the physics of exciton–Polariton condensates are now reviewed.
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Polariton lasing vs photon lasing in a semiconductor microcavity
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Hui Deng, Gregor Weihs, Yoshihisa Yamamoto, D W Snoke, J BlochAbstract:Nearly one decade after the first observation of Bose–Einstein condensation in atom vapors and realization of matter-wave (atom) lasers, similar concepts have been demonstrated recently for Polaritons: half-matter, half-light quasiparticles in semiconductor microcavities. The half-light nature of Polaritons makes Polariton lasers promising as a new source of coherent and nonclassical light with extremely low threshold energy. The half-matter nature makes Polariton lasers a unique test bed for many-body theories and cavity quantum electrodynamics. In this article, we present a series of experimental studies of a Polariton laser, exploring its properties as a relatively dense degenerate Bose gas and comparing it to a photon laser achieved in the same structure. The Polaritons have an effective mass that is twice the cavity photon effective mass, yet seven orders of magnitude less than the hydrogen atom mass; hence, they can potentially condense at temperatures seven orders of magnitude higher than those required for atom Bose–Einstein condensations. Accompanying the phase transition, a Polariton laser emits coherent light but at a threshold carrier density two orders of magnitude lower than that needed for a normal photon laser in a same structure. It also is shown that, beyond threshold, the Polariton population splits to a thermal equilibrium Bose–Einstein distribution at in-plane wave number k∥ > 0 and a nonequilibrium condensate at k∥ > 0, with a chemical potential approaching to zero. The spatial distributions and polarization characteristics of Polaritons also are discussed as unique signatures of a Polariton laser.
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Condensation of semiconductor microcavity exciton Polaritons
Science, 2002Co-Authors: Hui Deng, Gregor Weihs, Charles Santori, Jacqueline Bloch, Yoshihisa YamamotoAbstract:A phase transition from a classical thermal mixed state to a quantum-mechanical pure state of exciton Polaritons is observed in a GaAs multiple quantum-well microcavity from the decrease of the second-order coherence function. Supporting evidence is obtained from the observation of a nonlinear threshold behavior in the pump-intensity dependence of the emission, a Polariton-like dispersion relation above threshold, and a decrease of the relaxation time into the lower Polariton state. The condensation of microcavity exciton Polaritons is confirmed.
Stephane Kenacohen - One of the best experts on this subject based on the ideXlab platform.
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interacting Polariton fluids in a monolayer of tungsten disulfide
arXiv: Quantum Gases, 2018Co-Authors: Fábio Barachati, Antonio Fieramosca, Soroush Hafezian, Biswanath Chakraborty, Dario Ballarini, Ludvik Martinu, Vinod M. Menon, Daniele Sanvitto, Stephane KenacohenAbstract:Atomically thin transition metal dichalcogenides (TMDs) possess a number of properties that make them attractive for realizing room-temperature Polariton devices. An ideal platform for manipulating Polariton fluids within monolayer TMDs is that of Bloch surface waves, which confine the electric field to a small volume near the surface of a dielectric mirror. Here we demonstrate that monolayer tungsten disulfide ($\text{WS}_2$) can sustain Bloch surface wave Polaritons (BSWPs) with a Rabi splitting of 43 meV and propagation constants reaching 33 $\mu$m. In addition, we evidence strong Polariton-Polariton nonlinearities within BSWPs, which manifest themselves as a reversible blueshift of the lower Polariton resonance by up to 12.9$\pm$0.5 meV. Such nonlinearities are at the heart of Polariton devices and have not yet been demonstrated in TMD Polaritons. As a proof of concept, we use the nonlinearity to implement a nonlinear Polariton source. Our results demonstrate that BSWPs using TMDs can support long-range propagation combined with strong nonlinearities, enabling potential applications in integrated optical processing and Polaritonic circuits.
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nonlinear interactions in an organic Polariton condensate
Nature Materials, 2014Co-Authors: Konstantinos S Daskalakis, Stephane Kenacohen, Stefan A Maier, R MurrayAbstract:Cavity Polaritons have been extensively studied in inorganic materials. An organic Polariton condensate is now demonstrated to occur in the strongly interacting regime, at room temperature, in a cavity containing an organic polymer.
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room temperature Polariton lasing in an organic single crystal microcavity
Nature Photonics, 2010Co-Authors: Stephane Kenacohen, Stephen R ForrestAbstract:The optical properties of organic semiconductors are almost exclusively described using the Frenkel exciton picture1. In this description, the strong Coulombic interaction between an excited electron and the charged vacancy it leaves behind (a hole) is automatically taken into account. If, in an optical microcavity, the exciton–photon interaction is strong compared to the excitonic and photonic decay rates, a second quasiparticle, the microcavity Polariton, must be introduced to properly account for this coupling2. Coherent, laser-like emission from Polaritons has been predicted to occur when the ground-state occupancy of Polaritons 〈ngs〉, reaches 1 (ref. 3). This process, known as Polariton lasing, can occur at thresholds much lower than required for conventional lasing. Polaritons in organic semiconductors are highly stable at room temperature, but to our knowledge, there has as yet been no report of nonlinear emission from these structures. Here, we demonstrate Polariton lasing at room temperature in an organic microcavity composed of a melt-grown anthracene single crystal sandwiched between two dielectric mirrors. Polaritons in organic semiconductors are highly stable at room temperature, but so far nonlinear emission from these structures has not been demonstrated. Here, Polariton lasing at room temperature in an organic microcavity composed of a melt-grown anthracene single crystal sandwiched between two dielectric mirrors is reported.
Saul Velez - One of the best experts on this subject based on the ideXlab platform.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Saul Velez, Christopher Tollan, Zhigao DaiAbstract:Polaritons-hybrid light-matter excitations-enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3-5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light-matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics.
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in plane anisotropic and ultra low loss Polaritons in a natural van der waals crystal
Nature, 2018Co-Authors: Pablo Alonsogonzalez, Alexey Y Nikitin, Jian Yuan, Javier Martinsanchez, Javier Taboadagutierrez, Iban Amenabar, Shaojuan Li, Peining Li, Saul VelezAbstract:Polaritons—hybrid light–matter excitations—enable nanoscale control of light. Particularly large Polariton field confinement and long lifetimes can be found in graphene and materials consisting of two-dimensional layers bound by weak van der Waals forces1,2 (vdW materials). These Polaritons can be tuned by electric fields3,4 or by material thickness5, leading to applications including nanolasers6, tunable infrared and terahertz detectors7, and molecular sensors8. Polaritons with anisotropic propagation along the surface of vdW materials have been predicted, caused by in-plane anisotropic structural and electronic properties9. In such materials, elliptic and hyperbolic in-plane Polariton dispersion can be expected (for example, plasmon Polaritons in black phosphorus9), the latter leading to an enhanced density of optical states and ray-like directional propagation along the surface. However, observation of anisotropic Polariton propagation in natural materials has so far remained elusive. Here we report anisotropic Polariton propagation along the surface of α-MoO3, a natural vdW material. By infrared nano-imaging and nano-spectroscopy of semiconducting α-MoO3 flakes and disks, we visualize and verify phonon Polaritons with elliptic and hyperbolic in-plane dispersion, and with wavelengths (up to 60 times smaller than the corresponding photon wavelengths) comparable to those of graphene plasmon Polaritons and boron nitride phonon Polaritons3–5. From signal oscillations in real-space images we measure Polariton amplitude lifetimes of 8 picoseconds, which is more than ten times larger than that of graphene plasmon Polaritons at room temperature10. They are also a factor of about four larger than the best values so far reported for phonon Polaritons in isotopically engineered boron nitride11 and for graphene plasmon Polaritons at low temperatures12. In-plane anisotropic and ultra-low-loss Polaritons in vdW materials could enable directional and strong light–matter interactions, nanoscale directional energy transfer and integrated flat optics in applications ranging from bio-sensing to quantum nanophotonics. Observation of the anisotropic propagation of Polaritons along the surface of layered, semiconducting α-MoO3 confirms the existence of this phenomenon in natural materials.
