Ultracold atoms in optical lattices

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1 University Press Scholarship Online You are looking at 1-10 of 13 items for: keywords : optical lattices Ultracold atoms in optical lattices Immanuel Bloch in Many-Body Physics with Ultracold Gases: Lecture Notes of the Les Houches Summer School: Volume 94, July 2010 January 2013 ISBN: eisbn: acprof:oso/ This chapter provides an introduction to the field of strong correlation physics with ultracold atoms in optical lattices. After a basic introduction to the single-particle band structure and lattice configurations, the effect of strong interactions on the Hubbard model is discussed. Detection methods are introduced, which allow us to reveal in-trap density and (quasi)-momentum distributions, as well as correlations between particles on the lattice. The fundamental phases of the bosonic and fermionic Hubbard model are discussed. Superexchange spin-spin interactions that form the basis of quantum magnetism are introduced and the current status on observing such magnetic phenomena is highlighted. Finally, novel possibilities for detecting single-site and singleatom resolved quantum gases are outlined. Optical lattices and precise measurements Massimo Inguscio and Leonardo Fallani in Atomic Physics: Precise Measurements and Ultracold Matter Published in print: 2013 Published Online: ISBN: eisbn: acprof:oso/ This chapter discusses the physics of ultracold atoms trapped in optical lattices, i.e., ordered arrays of microscopic traps produced by the interference of counterpropagating laser beams. The motion of the atoms in these crystals of light can be described in terms of a periodic potential, similar to the one experienced by the electrons of an ideal crystalline solid. The chapter focuses on the physics of quantum Page 1 of 5

2 transport in optical lattices, which both provides a testing ground for ideal solid-state physics and constitutes an important resource for the determination of fundamental constants (e.g., the fine structure constant) and for the use of ultracold atoms as very precise sensors of forces (e.g., gravity). Atomic Bose fluids in optical lattices Nathan Gemelke and Cheng Chin in Novel Superfluids: Volume 2 Published in print: 2014 Published Online: March 2015 ISBN: eisbn: acprof:oso/ The physics of bosonic atoms in optical lattices is described. Starting from the basic experimental tools available to create such systems, the chapter introduces a simple model (known as the Bose Hubbard model) for such a system. A mean-field type picture is developed to determine the basic character of the superfluid and Mott-insulating phases, and the physical conditions under which each should arise. A number of experimental methods are outlined to detect the properties of the gas. The fact that two thermodynamic ground states exist at zero temperature with different types of order implies the existence of a quantum phase transition. The behavior of the gas near this transition is described using an entirely different framework quantum criticality formed around the concepts of scaling symmetry and the renormalization group. The Bose alkali gases A.J. Leggett in Quantum Liquids: Bose condensation and Cooper pairing in condensedmatter systems Published in print: 2006 Published Online: January 2008 ISBN: eisbn: acprof:oso/ This chapter starts with a discussion of the structure and properties of individual alkali atoms, and of trapping and diagnostic techniques. It is shown that under the conditions normally satisfied in practice, it is an excellent approximation to model the interatomic interaction by a deltafunction potential with a coefficient derived from the experimentally measured s-wave scattering length. The simplest theory of a Bose- Page 2 of 5

3 condensed dilute atomic alkali gas, the Gross-Pitaevskii ansatz, is introduced and some of its consequences explored. A number of spectacular phenomena related to the phase coherence of a gas displaying BEC are reviewed. The final two sections examine the behavior of an ultracold Bose gas in an optical lattice, and various signatures of superfluidity in the experimental systems. Optical lattices and quantum simulation Massimo Inguscio and Leonardo Fallani in Atomic Physics: Precise Measurements and Ultracold Matter Published in print: 2013 Published Online: ISBN: eisbn: acprof:oso/ This chapter extends the investigation of ultracold atoms in optical lattices to the emerging field of quantum simulation, in which atoms are used to experimentally realize basic condensed-matter models to precisely investigate their properties and their quantum phase transitions in an ultimately clean setting, where decoherence or unwanted interactions with the environment can be avoided. The chapter discusses the superfluid/metal-to-insulator transition exhibited by strongly-interacting atoms realizing Hubbard models, as well as the Anderson localization determining the suppression of transport for atoms moving in a disordered potential. It concludes with an illustration of the most recent developments in the field, discussing novel experimental techniques and important frontiers in this research. Ultracold gases in optical lattices: basic concepts in Ultracold Atoms in Optical Lattices: Simulating quantum many-body systems acprof:oso/ This chapter describes basic methods to realise optical potentials and optical lattices, listing in detail what can be controlled in ultracold atomic systems. It revisits the properties of non-interacting particles in periodic lattices: band structure, Bloch functions, and Wannier states. The chapter derives the Hubbard model in the tight binding approximation, and discusses Bose Einstein condensates in optical lattices in a weak interacting limit, and in a strongly correlated regime. Page 3 of 5

4 Perspectives: beyond standard optical lattices in Ultracold Atoms in Optical Lattices: Simulating quantum many-body systems acprof:oso/ This chapter presents a detailed report from the recent Program that was held in the fall of 2011 at Kavli Institute of Theoretical Physics called Beyond standard optical lattices. It describes some new trends in the physics of ultracold atoms that were not covered in this book (such as orbital lattices, non-fermi liquids, and Bose metals), as well as looking at standard optical lattices. Theory of dipolar gases Luis Santos in Many-Body Physics with Ultracold Gases: Lecture Notes of the Les Houches Summer School: Volume 94, July 2010 January 2013 ISBN: eisbn: acprof:oso/ This chapter discusses some interesting features of the physics of dipolar gases, with a particular emphasis on those phenomena that differ qualitatively from those known in non-dipolar gases. It covers the dipoledipole interaction, dipolar Bose Einstein condensates, and dipolar gases in optical lattices. Ultracold Atoms in Optical Lattices: Simulating quantum manybody systems Item type: book acprof:oso/ Quantum computers, although not yet available on the market, will revolutionise the future of information processing. Already now, quantum computers of special purpose, i.e., quantum simulators, are within reach. The physics of ultracold atoms, ions, and molecules offers unprecedented possibilities of control of quantum many systems, and Page 4 of 5

5 novel possibilities of applications for quantum information and quantum metrology. Particularly fascinating is the possibility of using ultracold atoms in lattices to simulate condensed matter or even high energy physics. This book provides a comprehensive overview of ultracold lattice gases as quantum simulators, an interdisciplinary field involving atomic, molecular, and optical physics; quantum optics; quantum information; and condensed matter and high energy physics. It includes some introductory chapters on basic concepts and methods, and focuses on the physics of spinor, dipolar, disordered, and frustrated lattice gases, before reviewing in detail artificial lattice gauge fields with ultracold gases. The last part of the book moves onto a discussion of possible implementations universal quantum computers with ultracold atoms. After a crash course in quantum information theory, several models of quantum computation with ultracold gases are presented, as well as the current understanding of condensed matter from a quantum information perspective. The book ends with the general discussion of various detection methods that are unique for ultracold atoms. Novel Superfluids: Volume 2 Karl-Heinz Bennemann and John B. Ketterson (eds) Published in print: 2014 Published Online: March 2015 ISBN: eisbn: Item type: book acprof:oso/ This volume continues the presentation of recent results on superfluids, including novel metallic systems, superfluid liquids, and atomic/molecular gases of bosons and fermions, particularly when trapped in optical lattices. Since the discovery of superconductivity (Leyden, 1911), superfluid4 He (Moscow and Cambridge, 1937), superfluid3 He (Cornell, 1972), and observation Bose Einstein condensation (BEC) of a gas (Colorado and MIT, 1995), the phenomenon of superfluidity has remained one of the most important topics in physics. Again and again, novel superfluids yield surprising and interesting behaviors. The many classes of metallic superconductors, including the high temperature perovskitebased oxides, MgB2, organic systems, and Fe-based pnictides, continue to offer challenges; the technical applications grow steadily. What the temperature and field limits are remains elusive. Atomic nuclei, neutron stars, and the Universe itself all involve various aspects of superfluidity; clearly the lessons learned have had a broad impact on physics as a whole. Page 5 of 5