Download or read book Realizing Quantum Spin Models with 7Li Atoms in an Optical Lattice written by Ivana Ljubomirova Dimitrova and published by . This book was released on 2020 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum spin Hamiltonians are paradigmatic models, which display different kinds of quantum phase transitions, strongly-correlated and topological ground states, and various regimes of transport. Expanding their significance, many mappings exist between quantum spin models and other systems in different areas of physics, mathematics, and beyond. Even though quantum spin models have been studied extensively, there are still many open questions. Simulating these Hamiltonians with the system of ultracold atoms in optical lattices provides a new perspective with the wide tunability of parameters and the minimal coupling to the environment. The mapping involves using the Mott insulating state of ultracold atoms in optical lattices, where the energy of a second-order tunneling process (superexchange) maps to the parameters of a Heisenberg model. This thesis provides a detailed roadmap for the design and building of such a quantum simulator with 7Li atoms in optical lattices. Each step of the process is described, together with the methods and techniques used for the building and the characterization of the physical system. A focus is placed on using the Mott insulator as a starting point for spin physics experiments and, in particular, on the characterization and improvements of the mapping from a density sector description to a spin sector description of the system. Several schemes for implementing and studying spin systems are presented. In particular, the feasibility of implementing the Heisenberg spin-1/2 and spin-1 models in this system is described. The tilted lattice is presented as a tool for studying pure superexchange-driven dynamics and for increasing their timescale by suppressing first order tunneling and the role of number defects. The first measurements and the tuning with this machine of superexchange-driven dynamics over a wide range in the anisotropic Heisenberg spin-1/2 models are presented. Finally, the versatility of the BEC 5 machine is showcased by a study which does not involve an optical lattice. It explores the realization of an exotic quantum phase, a supersolid, in a new way. After many years of building and improvements, the BEC 5 machine emerges as a repeatable and reliable quantum simulator which has a clear scientific agenda of exploring many-body ground states and non-equilibrium dynamics.

Download or read book Few and Many body Physics of Dipoles in Ion Traps and Optical Lattice Simulators written by Arghavan Safavi-Naini and published by . This book was released on 2014 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The presence of strong interactions in quantum many-body systems makes the analytical treatment of such systems very difficult. In this thesis we explore two possible proposals for simulating strongly correlated, quantum many-body systems: quantum simulations using trapped-ion quantum computers, and optical lattice simulators. In the first part of the thesis we describe the recent advances in Quantum Information Processing. In particular, we focus on the trapped-ion quantum computer. One of the main experimental roadblocks for this architecture is the "anomalous heating". This refers to the motional heating of the ion after being cooled to its ground state. In this thesis we present the first ab-initio and microscopic model for this noise. This model attributes the noise to fluctuating dipoles formed by adsorbates bound on the trap surface. The second part of the thesis studies three different lattice boson systems. First, we study the Bose-Hubbard model for hard-core bosons, interacting via dipole-dipole interactions. The resulting extended Bose-Hubbard model can be experimentally realized by polar molecules, Rydberg atoms, or magnetic dipoles in optical lattices. We use quantum Monte Carlo simulations, using the two-worm algorithm to study the ground-state phase diagram of dipolar, hard-core bosons, trapped in a bilayer geometry. Each layer is a quasi two-dimensional lattice, the dipole are aligned perpendicular to the layer, and inter-layer hopping is suppressed. We present zero- and finite-temperature results. Next we use a novel multiworm algorithm, along with bosonization, to study the ground-state phase diagram of bosons trapped in a stack of one-dimensional tubes. We study two different inter-particle interactions. First, we consider nearest-neighbor attractive interactions between the layers, and set the intra-layer interactions to zero. Next we study dipolar bosons with their dipole moments aligned perpendicular to the tube axis. Inter-layer tunneling is suppressed in both cases. Finally, we explore the possibility of using few-body phenomena to create exotic quantum many-body systems. We present a novel scheme to realize a tunable, onsite, three-body interaction. We study the resulting extended Bose-Hubbard model with a three-body on-site term using the Gutzwiller mean-field method, as well as quantum Monte Carlo simulations using the Worm algorithm.

Download or read book Probing and Preparing Novel States of Quantum Degenerate Rubidium Atoms in Optical Lattices written by Hirokazu Miyake and published by . This book was released on 2013 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultracold atoms in optical lattices are promising systems to realize and study novel quantum mechanical phases of matter with the control and precision offered by atomic physics. Towards this goal, as important as engineering new states of matter is the need to develop new techniques to probe these systems. I first describe our work on realizing Bragg scattering of infrared light from ultracold atoms in optical lattices. This is a detection technique which probes the spatial ordering of a crystalline system, and has led to our observation of Heisenberg limited wavefunction dynamics. Furthermore, we have observed the superfluid to Mott insulator transition through the matter wave Talbot effect. This technique will be particularly powerful for studying antiferromagnetic phases of matter due to its sensitivity to the crystalline composition. The second major component of this thesis describes a new scheme to realize the Harper Hamiltonian. The Harper Hamiltonian is a model system which effectively describes electrons in a solid immersed in a very high magnetic field. The effective magnetic field manifests itself as a position-dependent phase in the motion of the constituent particles, which can be related to gauge fields and has strong connections to topological properties of materials. We describe how we can engineer the Harper Hamiltonian in a two-dimensional optical lattice with neutral atoms by creating a linear potential tilt and inducing Raman transitions between localized states. In situ measurements provide evidence that we have successfully created the Harper Hamiltonian, but further evidence is needed to confirm the creation of the ground state of this Hamiltonian.

Download or read book Ultracold Atoms in Optical Lattices written by Maciej Lewenstein and published by Oxford University Press. This book was released on 2012-03-08 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the physics of atoms frozen to ultralow temperatures and trapped in periodic light structures. It introduces the reader to the spectacular progress achieved on the field of ultracold gases and describes present and future challenges in condensed matter physics, high energy physics, and quantum computation.

Download or read book Open Quantum Spin Systems in Semiconductor Quantum Dots and Atoms in Optical Lattices written by Heike Schwager and published by . This book was released on 2012 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Creating Novel Quantum States of Ultracold Bosons in Optical Lattices written by Colin Joseph Kennedy and published by . This book was released on 2017 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultracold atoms in optical lattices are among the most developed platforms of interest for building quantum devices suitable for quantum simulation and quantum computation. Ultracold trapped atoms are advantageous because they are fundamentally indistinguishable qubits that can be prepared with high fidelity in well-defined states and read-out with similarly high fidelities. However, an outstanding challenge for ultracold atoms in optical lattices is to engineer interesting interactions and control the effects of heating that couple the system to states that lie outside the Hilbert space we wish to engineer. In this thesis, I describe a series of experiments and theoretical proposals that address several critical issues facing ultracold atoms in optical lattices. First, I describe experiments where the tunneling behavior of atoms in the lattice is modified to make our fundamentally neutral particles behave as though they are charged particles in a magnetic field. We show how engineering this interaction creates intrinsic degeneracy in the single particle spectrum of the many-body system and how to introduce strong interactions in the system with the goal of producing exotic many-body states such as a bosonic fractional quantum Hall states. Then, I discuss how this technique can be easily generalized to include spin and higher spatial dimensions in order to access a rich variety of new physics phenomena. Next, I report on the realization of a spin-1 Heisenberg Hamiltonian which emerges as the low energy effective theory describing spin ordering in the doubly-occupied Mott insulator of two spin components. This integer spin Heisenberg model is qualitatively different from the half-integer spin model because it contains a gapped, spin-insulating ground state for small inter-spin interaction energies which we call the spin Mott. Using a spin-dependent lattice to control the inter-spin interactions, we demonstrate high-fidelity, reversible loading of the spin-Mott phase and develop a probe of local spin correlations in order to demonstrate a spin entropy below 0.2 kB per spin. Progress on adiabatically driving the quantum phase transition from the spin Mott to the xy-ferromagnetic is discussed along with the progress towards the creation of a quantum gas microscope for single atom detection and manipulation..

Download or read book Ultra cold Atoms in Optical Lattices written by Richard Walters and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Designing Quantum Spin Orbital Liquids in Artificial Mott Insulators written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum spin-orbital liquids are elusive strongly correlated states of matter that emerge from quantum frustration between spin and orbital degrees of freedom. A promising route towards the observation of those states is the creation of artificial Mott insulators where antiferromagnetic correlations between spins and orbitals can be designed. We show that Coulomb impurity lattices on the surface of gapped honeycomb substrates, such as graphene on SiC, can be used to simulate SU(4) symmetric spin-orbital lattice models. We exploit the property that massive Dirac fermions form mid-gap bound states with spin and valley degeneracies in the vicinity of a Coulomb impurity. Due to electronic repulsion, the antiferromagnetic correlations of the impurity lattice are driven by a super-exchange interaction with SU(4) symmetry, which emerges from the bound states degeneracy at quarter filling. We propose that quantum spin-orbital liquids can be engineered in artificially designed solid-state systems at vastly higher temperatures than achievable in optical lattices with cold atoms. Lastly, we discuss the experimental setup and possible scenarios for candidate quantum spin-liquids in Coulomb impurity lattices of various geometries.

Download or read book Spin obit Coupling in Optical Superlattices written by Wujie Huang and published by . This book was released on 2016 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum simulation is emerging as an exciting and active frontier in atomic physics. It allows us not only to verify existing models with high precision, but also to engineer novel systems with strong correlations and exotic topologies. Recent efforts have been made to include synthetic gauge fields and spin-orbit couplings into ultracold quantum gas experiments, which would enable us to study the quantum Hall effect, topological insulators as well as topological superfluids. This thesis will describe the experimental implementation of a new spin-orbit coupled system using pseudospin-1/2 in an optical superlattices, as well as progress towards detecting the stripe phase in this system. The first part of this thesis describes the development of a new apparatus for performing quantum simulations with sodium and lithium in optical lattices. A quantum simulation program is challenging itself, therefore having a stable platform for preparing quantum gases is essential for this task. We'll describe our development in reliable and efficient production of sodium Bose-Einstein condensates and lithium degenerate Fermi gases, as well as the characterization of our optical lattice system in a superfluid to a Mott-insulator quantum phase transition. The dynamics of a Bloch oscillation in a tilted lattice has also been studied as an important step towards the implementation of synthetic magnetic fields in our system. The second part of this thesis describes the experimental realization of spin-orbit coupling in a pseudospin-1/2 system using an optical superlattice. This new scheme uses orbital states in a tilted double-well as the pseudospins, therefore does not require near-resonant Raman light to flip the spins and promise longer lifetimes compared to earlier spin-orbit coupling experiments in atomic gases. It also features a robust miscible ground state with stationary density stripes, which is closely related to the concept of supersolidity in condensed matter systems. We'll present our experimental implementation of this new system, signatures of the resonant spin-orbit coupling, as well as progress toward experimental detection of the stripe phase via Bragg scattering. This pseudospin-1/2 system could also be used for simulating quantum magnetism,and potentially novel models with topological properties and Majorana excitations.

Download or read book Photonics Volume 2 written by David L. Andrews and published by John Wiley & Sons. This book was released on 2015-01-28 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discusses the basic physical principles underlying thescience and technology of nanophotonics, its materials andstructures This volume presents nanophotonic structures and Materials.Nanophotonics is photonic science and technology that utilizeslight/matter interactions on the nanoscale where researchers arediscovering new phenomena and developing techniques that go wellbeyond what is possible with conventional photonics andelectronics.The topics discussed in this volume are: CavityPhotonics; Cold Atoms and Bose-Einstein Condensates; Displays;E-paper; Graphene; Integrated Photonics; Liquid Crystals;Metamaterials; Micro-and Nanostructure Fabrication; Nanomaterials;Nanotubes; Plasmonics; Quantum Dots; Spintronics; Thin FilmOptics Comprehensive and accessible coverage of the whole of modernphotonics Emphasizes processes and applications that specifically exploitphoton attributes of light Deals with the rapidly advancing area of modern optics Chapters are written by top scientists in their field Written for the graduate level student in physical sciences;Industrial and academic researchers in photonics, graduate studentsin the area; College lecturers, educators, policymakers,consultants, Scientific and technical libraries, governmentlaboratories, NIH.

Download or read book Manipulating Quantum Systems written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2020-09-14 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of atomic, molecular, and optical (AMO) science underpins many technologies and continues to progress at an exciting pace for both scientific discoveries and technological innovations. AMO physics studies the fundamental building blocks of functioning matter to help advance the understanding of the universe. It is a foundational discipline within the physical sciences, relating to atoms and their constituents, to molecules, and to light at the quantum level. AMO physics combines fundamental research with practical application, coupling fundamental scientific discovery to rapidly evolving technological advances, innovation and commercialization. Due to the wide-reaching intellectual, societal, and economical impact of AMO, it is important to review recent advances and future opportunities in AMO physics. Manipulating Quantum Systems: An Assessment of Atomic, Molecular, and Optical Physics in the United States assesses opportunities in AMO science and technology over the coming decade. Key topics in this report include tools made of light; emerging phenomena from few- to many-body systems; the foundations of quantum information science and technologies; quantum dynamics in the time and frequency domains; precision and the nature of the universe, and the broader impact of AMO science.

Download or read book Lectures on Quantum Information written by Dagmar Bruss and published by Wiley-VCH. This book was released on 2007 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum Information Processing is a young and rapidly growing field of research at the intersection of physics, mathematics, and computer science. Its ultimate goal is to harness quantum physics to conceive -- and ultimately build -- "quantum" computers that would dramatically overtake the capabilities of today's "classical" computers. One example of the power of a quantum computer is its ability to efficiently find the prime factors of a larger integer, thus shaking the supposedly secure foundations of standard encryption schemes. This comprehensive textbook on the rapidly advancing field introduces readers to the fundamental concepts of information theory and quantum entanglement, taking into account the current state of research and development. It thus covers all current concepts in quantum computing, both theoretical and experimental, before moving on to the latest implementations of quantum computing and communication protocols. With its series of exercises, this is ideal reading for students and lecturers in physics and informatics, as well as experimental and theoretical physicists, and physicists in industry. Dagmar Bruß graduated at RWTH University Aachen, Germany, and received her PhD in theoretical particle physics from the University of Heidelberg in 1994. As a research fellow at the University of Oxford she started to work in quantum information theory. Another fellowship at ISI Torino, Italy, followed. While being a research assistant at the University of Hannover she completed her habilitation. Since 2004 Professor Bruß has been holding a chair at the Institute of Theoretical Physics at the Heinrich-Heine-University Düsseldorf, Germany. Gerd Leuchs studied physics and mathematics at the University of Cologne, Germany, and received his Ph.D. in 1978. After two research visits at the University of Colorado in Boulder, USA, he headed the German gravitational wave detection group from 1985 to 1989. He became technical director at Nanomach AG in Switzerland. Since 1994 Professor Leuchs has been holding the chair for optics at the Friedrich-Alexander-University of Erlangen-Nuremberg, Germany. His fields of research span the range from modern aspects of classical optics to quantum optics and quantum information. Since 2003 he has been Director of the Max Planck Research Group for Optics, Information and Photonics at Erlangen.

Download or read book Ultracold Bosonic and Fermionic Gases written by Kathy Levin and published by Elsevier. This book was released on 2012-11-15 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapidly developing topic of ultracold atoms has many actual and potential applications for condensed-matter science, and the contributions to this book emphasize these connections. Ultracold Bose and Fermi quantum gases are introduced at a level appropriate for first-year graduate students and non-specialists such as more mature general physicists. The reader will find answers to questions like: how are experiments conducted and how are the results interpreted? What are the advantages and limitations of ultracold atoms in studying many-body physics? How do experiments on ultracold atoms facilitate novel scientific opportunities relevant to the condensed-matted community? This volume seeks to be comprehensible rather than comprehensive; it aims at the level of a colloquium, accessible to outside readers, containing only minimal equations and limited references. In large part, it relies on many beautiful experiments from the past fifteen years and their very fruitful interplay with basic theoretical ideas. In this particular context, phenomena most relevant to condensed-matter science have been emphasized. - Introduces ultracold Bose and Fermi quantum gases at a level appropriate for non-specialists - Discusses landmark experiments and their fruitful interplay with basic theoretical ideas - Comprehensible rather than comprehensive, containing only minimal equations

Download or read book Condensazione Di Bose Einstein Nei Gas Atomici written by M. Inguscio and published by . This book was released on 1999 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Introduction to Frustrated Magnetism written by Claudine Lacroix and published by Springer Science & Business Media. This book was released on 2011-01-12 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of highly frustrated magnetism has developed considerably and expanded over the last 15 years. Issuing from canonical geometric frustration of interactions, it now extends over other aspects with many degrees of freedom such as magneto-elastic couplings, orbital degrees of freedom, dilution effects, and electron doping. Its is thus shown here that the concept of frustration impacts on many other fields in physics than magnetism. This book represents a state-of-the-art review aimed at a broad audience with tutorial chapters and more topical ones, encompassing solid-state chemistry, experimental and theoretical physics.

Download or read book Hubbard Model The Recent Results written by Mario G Rasetti and published by World Scientific. This book was released on 1991-07-03 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of articles provides authoritative and up-to-date reviews on the Hubbard Model. It will be useful to graduate students and researchers in the field.

Download or read book A Primer on Quantum Fluids written by Carlo F. Barenghi and published by Springer. This book was released on 2016-08-10 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this primer is to cover the essential theoretical information, quickly and concisely, in order to enable senior undergraduate and beginning graduate students to tackle projects in topical research areas of quantum fluids, for example, solitons, vortices and collective modes. The selection of the material, both regarding the content and level of presentation, draws on the authors analysis of the success of relevant research projects with newcomers to the field, as well as of the students feedback from many taught and self-study courses on the subject matter. Starting with a brief historical overview, this text covers particle statistics, weakly interacting condensates and their dynamics and finally superfluid helium and quantum turbulence. At the end of each chapter (apart from the first) there are some exercises. Detailed solutions can be made available to instructors upon request to the authors.