The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Franco Nori - One of the best experts on this subject based on the ideXlab platform.
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Atomic Physics and quantum optics using superconducting circuits
The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting, 2013Co-Authors: Franco Nori, J. Q. YouAbstract:Superconducting circuits [1-11] based on Josephson junctions exhibit macroscopic quantum coherence and can behave like artificial atoms. Recent technological advances have made it possible to implement Atomic-Physics and quantum-optics experiments on a chip using these artificial atoms. This pedagogical talk presents a brief introduction to this rapidly advancing field. We not only discuss phenomena analogous to those in Atomic Physics and quantum optics with natural atoms, but also highlight those not occurring in natural atoms.
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Atomic Physics and quantum optics using superconducting circuits
Nature, 2011Co-Authors: J. Q. You, Franco NoriAbstract:Superconducting circuits based on Josephson junctions exhibit macroscopic quantum coherence and can behave like artificial atoms. Recent technological advances have made it possible to implement Atomic-Physics and quantum-optics experiments on a chip using these artificial atoms. This Review presents a brief overview of the progress achieved so far in this rapidly advancing field. We not only discuss phenomena analogous to those in Atomic Physics and quantum optics with natural atoms, but also highlight those not occurring in natural atoms. In addition, we summarize several prospective directions in this emerging interdisciplinary field.
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superconducting circuits and quantum information
Physics Today, 2005Co-Authors: Franco NoriAbstract:Superconducting circuits can behave like atoms making transitions between two levels. Such circuits can test quantum mechanics at macroscopic scales and be used to conduct Atomic-Physics experiments on a silicon chip.
J. Dalibard - One of the best experts on this subject based on the ideXlab platform.
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Two-dimensional Bose fluids: An Atomic Physics perspective
La Rivista del Nuovo Cimento, 2011Co-Authors: Z. Hadzibabic, J. DalibardAbstract:We give in this lecture an introduction to the Physics of two-dimensional (2d) Bose gases. We first discuss the properties of uniform, infinite 2d Bose fluids at non-zero temperature T . We explain why thermal fluctuations are strong enough to destroy the fully ordered state associated with Bose-Einstein condensation, but are not strong enough to suppress superfluidity in an interacting system at low T . We present the basics of the Berezinskii-Kosterlitz-Thouless theory, which provides the general framework for understanding 2d superfluidity. We then turn to experimentally relevant finite-size systems, in which the presence of residual “quasi–long-range” order at low temperatures leads to an interesting interplay between superfluidity and condensation. Finally we summarize the recent progress in theoretical understanding and experimental investigation of ultracold Atomic gases confined to a quasi-2d geometry.
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two dimensional bose fluids an Atomic Physics perspective
arXiv: Quantum Gases, 2009Co-Authors: Z. Hadzibabic, J. DalibardAbstract:The properties of phase transitions and the types of order present in the low-temperature states of matter are fundamentally dependent on the dimensionality of physical systems. Generally, highly ordered states are more robust in higher dimensions, while thermal and quantum fluctuations, which favour disordered states, play a more important role in lower dimensions. The case of a two-dimensional (2d) Bose fluid is particularly fascinating because of its "marginal" behaviour. In an infinite uniform 2d fluid thermal fluctuations at any non-zero temperature are strong enough to destroy the fully ordered state associated with Bose--Einstein condensation, but are not strong enough to suppress superfluidity in an interacting system at low, but non-zero temperatures. Further, the presence of residual "quasi-long-range" order at low temperatures leads to an interesting interplay between superfluidity and condensation in all experimentally relevant finite-size systems. In these notes we give an introduction to the Physics of 2d Bose fluids from an Atomic Physics perspective. Our goal is to summarize the recent progress in theoretical understanding and experimental investigation of ultra-cold Atomic gases confined to 2d geometry, and we also hope to provide a useful introduction to these systems for researchers working on related topics in other fields of Physics.
P L Knight - One of the best experts on this subject based on the ideXlab platform.
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Atomic Physics with super high intensity lasers
Reports on Progress in Physics, 1997Co-Authors: M Protopapas, Christoph H Keitel, P L KnightAbstract:We review the phenonomena which occur in multiphoton Physics when the electric field of the applied laser radiation becomes comparable with the Coulomb field strength seen by an electron in the ground state of Atomic hydrogen. This field is reached at an irradiance of approximately . The normal perturbative photon-by-photon based picture of the interaction of individual electrons with the field is replaced by a tunnelling picture in which, in a time of the order of, or less than one optical cycle, Atomic wavepackets are generated which escape the confining Coulomb potential. These wavepackets are strongly influenced by the laser, `quiver' and may be accelerated back to the parent ion in a recollision process. Phase-coherent effects locked to the laser field become important: high harmonics are generated from these recollisions. We discuss the theory of such effects, and review progress in understanding how this quiver motion can be coherently controlled. We discuss ionization dynamics and review mechanisms by which atoms may be stabilized in very strong fields. Finally, we discuss relativistic effects which occur at very high-intensities.
Z. Hadzibabic - One of the best experts on this subject based on the ideXlab platform.
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Two-dimensional Bose fluids: An Atomic Physics perspective
La Rivista del Nuovo Cimento, 2011Co-Authors: Z. Hadzibabic, J. DalibardAbstract:We give in this lecture an introduction to the Physics of two-dimensional (2d) Bose gases. We first discuss the properties of uniform, infinite 2d Bose fluids at non-zero temperature T . We explain why thermal fluctuations are strong enough to destroy the fully ordered state associated with Bose-Einstein condensation, but are not strong enough to suppress superfluidity in an interacting system at low T . We present the basics of the Berezinskii-Kosterlitz-Thouless theory, which provides the general framework for understanding 2d superfluidity. We then turn to experimentally relevant finite-size systems, in which the presence of residual “quasi–long-range” order at low temperatures leads to an interesting interplay between superfluidity and condensation. Finally we summarize the recent progress in theoretical understanding and experimental investigation of ultracold Atomic gases confined to a quasi-2d geometry.
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two dimensional bose fluids an Atomic Physics perspective
arXiv: Quantum Gases, 2009Co-Authors: Z. Hadzibabic, J. DalibardAbstract:The properties of phase transitions and the types of order present in the low-temperature states of matter are fundamentally dependent on the dimensionality of physical systems. Generally, highly ordered states are more robust in higher dimensions, while thermal and quantum fluctuations, which favour disordered states, play a more important role in lower dimensions. The case of a two-dimensional (2d) Bose fluid is particularly fascinating because of its "marginal" behaviour. In an infinite uniform 2d fluid thermal fluctuations at any non-zero temperature are strong enough to destroy the fully ordered state associated with Bose--Einstein condensation, but are not strong enough to suppress superfluidity in an interacting system at low, but non-zero temperatures. Further, the presence of residual "quasi-long-range" order at low temperatures leads to an interesting interplay between superfluidity and condensation in all experimentally relevant finite-size systems. In these notes we give an introduction to the Physics of 2d Bose fluids from an Atomic Physics perspective. Our goal is to summarize the recent progress in theoretical understanding and experimental investigation of ultra-cold Atomic gases confined to 2d geometry, and we also hope to provide a useful introduction to these systems for researchers working on related topics in other fields of Physics.
Roberto Gangemi - One of the best experts on this subject based on the ideXlab platform.
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electronic trajectories in Atomic Physics the chemical bond in the h 2 ion
Chaos, 2020Co-Authors: A Carati, L Galgani, Fabrizio Gangemi, Roberto GangemiAbstract:The H 2 + ion is the simplest example in which a chemical bond exists, created by one electron between two protons. As all chemical bonds, it is usually considered inexplicable in a classical frame. Here, in view of the extremely large velocities attained by the electron near the protons, we consider a relativistic extension of the standard classical three-body model. This has a great impact since the reference unperturbed system (clamped protons) is no more integrable, and indeed by molecular dynamics simulations, we find that the modification entails the existence of a large region of strongly chaotic motions for the unperturbed system, which lead, for the full system, to a collapse of the molecule. For motions of generic type, with the electron bouncing between the protons, there exists an open region of motions regular enough for producing a bond. Such a region is characterized by the property that the electron’s trajectories have an angular momentum p φ along the inter-nuclear axis of the order of the reduced Planck’s constant ℏ. Moreover, special initial data exist for which the experimental bond length and oscillation frequency of the protons (but not the dissociation energy) are well reproduced. Also, well reproduced is the quantum potential, albeit only in an extended interval about the minimum.