This paper reviews recent experimental and theoretical progress concerning many-body phenomena in dilute, ultracold gases. It focuses on effects beyond standard weak-coupling descriptions, such as the Mott-Hubbard transition in optical lattices, strongly interacting gases in one and two dimensions, or lowest-Landau-level physics in quasi-two-dimensional gases in fast rotation. Strong correlations in fermionic gases are discussed in optical lattices or near-Feshbach resonances in the BCS-BEC crossover.

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Many-Body Physics with Ultracold Gases

The Classical Field Theories

Graphene is one of the most promising materials in nanotechnology. The electronic and mechanical properties of graphene samples with high perfection of the atomic lattice are outstanding, but structural defects, which may appear during growth or processing, deteriorate the performance of graphene-based devices. However, deviations from perfection can be useful in some applications, as they make it possible to tailor the local properties of graphene and to achieve new functionalities. In this article, the present knowledge about point and line defects in graphene are reviewed. Particular emphasis is put on the unique ability of graphene to reconstruct its lattice around intrinsic defects, leading to interesting effects and potential applications. Extrinsic defects such as foreign atoms which are of equally high importance for designing graphene-based devices with dedicated properties are also discussed.

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Structural defects in graphene

Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases. They have found numerous experimental applications, opening up the way to important breakthroughs. This review broadly covers the phenomenon of Feshbach resonances in ultracold gases and their main applications. This includes the theoretical background and models for the description of Feshbach resonances, the experimental methods to find and characterize the resonances, a discussion of the main properties of resonances in various atomic species and mixed atomic species systems, and an overview of key experiments with atomic Bose-Einstein condensates, degenerate Fermi gases, and ultracold molecules.

Feshbach resonances in ultracold gases

Modern nanotechnology allows one to scale down various important devices (sensors, chips, fibers, etc.) and thus opens up new horizons for their applications. The efficiency of most of them is based on fundamental physical phenomena, such as transport of wave excitations and resonances. Short propagation distances make phase-coherent processes of waves important. Often the scattering of waves involves propagation along different paths and, as a consequence, results in interference phenomena, where constructive interference corresponds to resonant enhancement and destructive interference to resonant suppression of the transmission. Recently, a variety of experimental and theoretical work has revealed such patterns in different physical settings. The purpose of this review is to relate resonant scattering to Fano resonances, known from atomic physics. One of the main features of the Fano resonance is its asymmetric line profile. The asymmetry originates from a close coexistence of resonant transmission and resonant reflection and can be reduced to the interaction of a discrete (localized) state with a continuum of propagation modes. The basic concepts of Fano resonances are introduced, their geometrical and/or dynamical origin are explained, and theoretical and experimental studies of light propagation in photonic devices, charge transport through quantum dots, plasmon scattering in Josephson-junction networks, and matter-wave scattering in ultracold atom systems, among others are reviewed.

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Fano resonances in nanoscale structures

Deep inelastic cross sections in the statistical multistep direct formalism

Overview, Victor Weisskopf Niels Bohr and the development of physics, A.Pais on the origins of the Copenhagen interpretation, Arthur I.Miller Niels Bohr and atomic physics today, Daniel Kleppner condensed matter physics - does quantum mechanics matter?, Michael E.Fisher nuclear physics - comments and reflections, Herman Feshbach the new ether, J.D.Bjorken recent developments in cosmology, George Field black holes and the foundations of quantum mechanics, Gerard't Hooft do black holes emit black body radiation?, T.D.Lee quarternionic quantum field theory, Stephen L.Adler light and life - Niels Bohr's legacy to contemporary biology, Gunther S.Stent Bertlmann's socks and the nature of reality, J.S.Bell fifty years later - when gedanken experiments become real experiments, Alain Aspect Philippe Grangier physical and philosophical issues in the Bohr-Einstein debate, Abner Shimony the Soviet reaction to Bohr's quantum mechanics, Loren R.Graham Niels Bohr and the first principles of arms control, Martin J.Sherwin American attitudes on security - comments, John Steinbruner science, technology and the arms race - European perspectives, Edoardo Amaldi.

Niels Bohr, physics and the world : proceedings of the Niels Bohr Centennial Symposium, Boston, Massachusetts, USA., November 12-14, 1985, American Academy of Arts and Sciences, Cambridge, Massachusetts

Friction and the optical model

A recently developed boundary shape perturbation theory has been applied to the calculation of acoustic normal frequencies and wave patterns in enclosures which deviate somewhat from rectangularity. The method is quite general; it is applicable to any form of irregularity if the amount of distortion is “small,” provided solutions for the basic form are obtainable. Specific formulas have been derived for trapezoidal and parallelogram shapes. Calculated frequencies and wave patterns are found to agree closely with experimentally measured values reported previously. An experiment has been devised to test the range of validity of the perturbation calculations for one case. A small test chamber was built with walls which could be shifted continuously in plan to give trapezoids of constant area, but having any desired degree of deformity between a rectangle AB and an isosceles triangle of base 2A and height B. A number of normal frequencies were traced through the whole range of shapes. For wall angle shifts up...

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Herman Feshbach

Papers

Deep inelastic cross sections in the statistical multistep direct formalism

Niels Bohr, physics and the world : proceedings of the Niels Bohr Centennial Symposium, Boston, Massachusetts, USA., November 12-14, 1985, American Academy of Arts and Sciences, Cambridge, Massachusetts

Friction and the optical model

On the Perturbation of Normal Modes of Vibration

Spin and isospin effects in elastic P-4He scattering near 1 GeV☆