The Experts below are selected from a list of 86619 Experts worldwide ranked by ideXlab platform
Oriol Arteaga - One of the best experts on this subject based on the ideXlab platform.
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light Scattering by coupled oriented dipoles decomposition of the Scattering Matrix
Physical Review B, 2018Co-Authors: Ali M Kuntman, Ertan Kuntman, Jordi Sanchoparramon, Oriol ArteagaAbstract:We study the optical response of two coupled oriented dipoles with the dimer axis perpendicular to the wave vector of light by analyzing how their Scattering Matrix can be decomposed. The Scattering Matrix can be written as a linear combination of three terms with a clear physical meaning: one for each particle and another that is responsible for the coupling and that vanishes for noninteracting or distant particles. We show that the interaction term may generate optical activity for certain Scattering directions and that this effect manifests itself mostly in the near field. This simple and intuitive theory based on Matrix and vector states of oriented dipoles also describes hybridization processes and Fano resonances. The decomposition method can be also formulated in terms of a hybrid basis that allows us to quantitatively determine the individual contribution of the in-phase and out-of-phase coupling modes to the overall intensity. Our method can help to understand the optical response of more complex nanostructures that can be decomposed into dipole terms. The results are illustrated in gold nanoantenna dimers which exhibit a strong dipolar resonance.
G B Lesovik - One of the best experts on this subject based on the ideXlab platform.
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Scattering Matrix approach to the description of quantum electron transport
arXiv: Mesoscale and Nanoscale Physics, 2014Co-Authors: G B Lesovik, Ivan SadovskyyAbstract:We consider the Scattering Matrix approach to quantum electron transport in meso- and nano-conductors. This approach is an alternative to the more conventional kinetic equation and Green's function approaches, and often is more efficient for coherent conductors (especially for proving general relations) and typically more transparent. We provide a description of both time-averaged quantities (for example, current-voltage characteristics) and current fluctuations in time -- noise, as well as full counting statistics of charge transport in a finite time. In addition to normal conductors, we consider contacts with superconductors and Josephson junctions.
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Scattering Matrix approach to the description of quantum electron transport
Physics-Uspekhi, 2011Co-Authors: G B Lesovik, Ivan SadovskyyAbstract:We consider the Scattering Matrix approach to quantum electron transport in meso- and nanoconductors. This approach is an alternative to the more conventional kinetic equation and Green's function approaches, and is often more efficient for coherent conductors (especially when proving general relations) and typically more transparent. We provide a description of both time-averaged quantities (for example, current–voltage characteristics) and current fluctuations in time — noise, as well as full counting statistics of charge transport in a finite time. In addition to normal conductors, we consider contacts with superconductors and Josephson junstions.
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n particle Scattering Matrix for electrons interacting on a quantum dot
Physical Review Letters, 2008Co-Authors: A V Lebedev, G B Lesovik, G BlatterAbstract:We present a nonperturbative expression for the Scattering Matrix of N particles interacting inside a quantum dot. Characterizing the dot by its resonances, we find a compact form for the Scattering Matrix in a real-time representation. We study the transmission probabilities and interaction-induced orbital entanglement of two electrons incident on the dot in a spin-singlet state.
Anders Bernland - One of the best experts on this subject based on the ideXlab platform.
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bandwidth limitations for Scattering of higher order electromagnetic spherical waves with implications for the antenna Scattering Matrix
IEEE Transactions on Antennas and Propagation, 2012Co-Authors: Anders BernlandAbstract:Various physical limitations in electromagnetic theory and antenna theory have received considerable attention recently. However, there are no previous limitations on the Scattering of higher order electromagnetic vector spherical waves, despite the widespread use of spherical wave decompositions. In the present paper, bandwidth limitations on the Scattering Matrix are derived for a wide class of heterogeneous objects, in terms of their electrical size, shape and static material properties. In particular, it is seen that the order of the dominating term in the Rayleigh limit increases with the order of the spherical wave. Furthermore, it is shown how the limitations place bounds on the antenna Scattering Matrix, thus introducing a new approach to physical limitations on antennas. Comparisons to other types of antenna limitations are given, and numerical simulations for two folded spherical helix antennas and a directive Yagi-Uda antenna are included to illuminate and validate the theory. The results in this paper are derived using a general approach to derive limitations for passive systems: First, the low-frequency asymptotic expansion of the Scattering Matrix of a general scatterer is derived. This gives a set of sum rules, from which the limitations follow.
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bandwidth limitations for Scattering of higher order electromagnetic spherical waves with implications for the antenna Scattering Matrix
Technical Report LUTEDX (TEAT-7214) 1-23 (2011); TEAT-7214 (2011), 2011Co-Authors: Anders BernlandAbstract:Various physical limitations in electromagnetic theory and antenna theory have received considerable attention recently. However, there are no previous limitations on the Scattering of higher order electromagnetic vector spherical waves, despite the widespread use of spherical wave decompositions. In the present paper, bandwidth limitations on the Scattering Matrix are derived for a wide class of heterogeneous objects, in terms of their electrical size, shape and static material properties. In particular, it is seen that the order of the dominating term in the Rayleigh limit increases with the order of the spherical wave. Furthermore, it is shown how the limitations place bounds on the antenna Scattering Matrix, thus introducing a new approach to physical limitations on antennas. Comparisons to other types of antenna limitations are given, and numerical simulations for two folded spherical helix antennas and a directive Yagi-Uda antenna are included to illuminate and validate the theory. The results in this paper are derived using a general approach to derive limitations for passive systems: First, the low-frequency asymptotic expansion of the Scattering Matrix of a general scatterer is derived. This gives a set of sum rules, from which the limitations follow. (Less)
Ivan Sadovskyy - One of the best experts on this subject based on the ideXlab platform.
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Scattering Matrix approach to the description of quantum electron transport
arXiv: Mesoscale and Nanoscale Physics, 2014Co-Authors: G B Lesovik, Ivan SadovskyyAbstract:We consider the Scattering Matrix approach to quantum electron transport in meso- and nano-conductors. This approach is an alternative to the more conventional kinetic equation and Green's function approaches, and often is more efficient for coherent conductors (especially for proving general relations) and typically more transparent. We provide a description of both time-averaged quantities (for example, current-voltage characteristics) and current fluctuations in time -- noise, as well as full counting statistics of charge transport in a finite time. In addition to normal conductors, we consider contacts with superconductors and Josephson junctions.
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Scattering Matrix approach to the description of quantum electron transport
Physics-Uspekhi, 2011Co-Authors: G B Lesovik, Ivan SadovskyyAbstract:We consider the Scattering Matrix approach to quantum electron transport in meso- and nanoconductors. This approach is an alternative to the more conventional kinetic equation and Green's function approaches, and is often more efficient for coherent conductors (especially when proving general relations) and typically more transparent. We provide a description of both time-averaged quantities (for example, current–voltage characteristics) and current fluctuations in time — noise, as well as full counting statistics of charge transport in a finite time. In addition to normal conductors, we consider contacts with superconductors and Josephson junstions.
Nir Rotenberg - One of the best experts on this subject based on the ideXlab platform.
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experimental reconstruction of the few photon nonlinear Scattering Matrix from a single quantum dot in a nanophotonic waveguide
Physical Review Letters, 2021Co-Authors: Hanna Le Jeannic, Tomas Ramos, Signe F Simonsen, Tommaso Pregnolato, Zhe Liu, Rudiger Schott, A D Wieck, Arne Ludwig, Nir RotenbergAbstract:Coherent photon-emitter interfaces offer a way to mediate efficient nonlinear photon-photon interactions, much needed for quantum information processing. Here we experimentally study the case of a two-level emitter, a quantum dot, coupled to a single optical mode in a nanophotonic waveguide. We carry out few-photon transport experiments and record the statistics of the light to reconstruct the Scattering Matrix elements of one- and two-photon components. This provides direct insight to the complex nonlinear photon interaction that contains rich many-body physics.
