Quantum gases in optical lattices : the atomic Mott insulator

D. van Oosten

Published Sep 13, 2004• 5 citations

Abstract

An optical lattice is a periodic potential for atoms, created using a standing wave pattern of light. Due to the interaction between the light and the atoms, the atoms are attracted to either the nodes or the anti-nodes of the standing wave, depending on the exact wave lenght of the light. This means that if such a lattice is loaded with a sufficiently high number of ultracold atoms, a periodic array of atoms is obtained, we an interatomic distance of a few tenths of a micrometer. In order to obtain such a high number of cold atoms, one first has to create a so-called Bose-Einstein condensate. When an optical lattice is loaded from a Bose-Einstein condensate, it is possible to create a system in which every atom is in the lowest band of the lattice and there is on average one atom in each lattice site. Because the lattice potential is created with laser light, the depth of the lattice can easily be tuned by changing the intensity of the laser. When the intensity of the laser light is low, the atoms can tunnel from one site to the next. Due to this tunneling, the gas of atoms in the lattice will remain superfluid. However, if the intensity of the laser light is increased to above a certain critical value, a quantum phase transition occurs to a so-called Mott insulator. In this state, the atoms can no longer tunnel due to the fact that the on-site interaction between atoms becomes more important then the tunneling probability. In this PhD thesis, a description is given of the experimental setup that is being constructed in our group to create these systems in our lab. Also, a theoretical description is given of these systems and several important quantities our derived, such as the gap of the Mott-insulating state. Furthermore, an experiment is proposed that can be used to accurately measure this gap.

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Focus on Cold Atoms in Otical Lattices Contents Theory of Feshbach molecule formation in a dilute gas during a magnetic field ramp J E Williams, Nicolai Nygaard and Charles W Clark Dressed molecules in an optical lattice K B Gubbels, D B M Dickersheid and Henk T C Stoof Precision measurement of spin-dependent interaction strengths for spin-1 and spin-2 87 Rb atoms Artur Widera, Fabrice Gerbier, Simon Folling, Tatjana Gericke, Olaf Mandel and Immanuel Bloch The Fermi–Hubbard model at unitarity Evgeni Burovski, Nikolay Prokof'ev, B Svistunov and M Troyer Interaction broadening of wannier functions and mott transitions in atomic BEC Jinbin Li, Yue Yu, A M Dudarev and Qian Niu Hanbury Brown–Twiss interferometry for fractional and integer Mott phases Ana Maria Rey, I I Satija and Charles W Clark Quantum random walk with Rydberg atoms in an optical lattice Robin Cote, Alexander Russell, Edward E. Eyler and Phillip Gould Raman Spectroscopy of Mott insulator states in optical lattices P Blair Blakie Interacting Bose gases in quasi-one dimensional optical lattices M A Cazalilla, A F Ho and Thierry Giamarchi Long distance transport of ultracold atoms using a 1D optical lattice Stefan Schmid, Gregor Thalhammer, Klaus Winkler, Florian Lang and J H Denschlag Signatures of the superfluid to Mott-insulator transition in the excitation spectrum of ultracold atoms S R Clark and Dieter Jaksch Extended fermionization of 1D bosons in optical lattices Guido Pupillo, Ana Maria Rey, Carl J Williams and Charles W Clark One-dimensional description of a Bose–Einstein condensate in a rotating closed-loop waveguide Sylvain Schwartz, Marco Cozzini, Chiara Menotti, I Carusotto, Philippe Bouyer and Sandro Stringari Photo-ionization in far-off resonant optical lattices R M Potvliege and Charles S Adams Cooling toolbox for atoms in optical lattices Markus Popp, J J Garcia-Ripoll, K G Vollbrecht and J I Cirac Experimental study of the transport of coherent interacting matter-waves in a 1D random potential induced by laser speckle David Clement, A F Varon, J A Retter, L Sanchez-Palencia, Alain Aspect and P Bouyer Quantum dynamics, particle localization and instability of Mott states: the effect of fermion-boson conversion on Mott states Fei Zhou and Congjun Wu Off-diagonal correlations of lattice impenetrable bosons in one dimension D M Gangardt and Gora V Shlyapnikov Collective mode damping and viscosity in a 1D unitary Fermi gas Matthias Punk and W Zwerger Coherent matter waves emerging from Mott-insulators K Rodriguez, S R Manmana, Madrazo Marcos Rigol, R M Noack and A Muramatsu Phase-matched matter wave collisions in periodic potentials Klaus Moelmer Fermion pairing with spin-density imbalance in an optical lattice T Koponen, J Kinnunen, J-P Martikainen, L M Jensen and P Törmä Macroscopic superpositions of superfluid flows David W Hallwood, Keith Burnett and Jacob Dunningham Mean-field phase diagram of disordered bosons in a lattice at nonzero temperature K V Krutitsky, A Pelster and R Graham A primary noise thermometer for ultracold Bose gases R Gati, J Esteve, B Hemmerling, T B Ottenstein, J Appmeier, A Weller and M K Oberthaler Precision preparation of strings of trapped neutral atoms Y Miroshnychenko, W Alt, I Dotsenko, L Förster, M Khudaverdyan, A Rauschenbeutel and D Meschede Cold Fermi gases: a new perspective on spin-charge separation Corinna Kollath and Ulrich Schollwöck Analysis of localization phenomena in weakly interacting disordered lattice gases T Schulte, S Drenkelforth, J Kruse, R Tiemeyer, K Sacha, J Zakrzewski, M Lewenstein, W Ertmer and J J Arlt Localization and anomalous transport in a 1D soft boson optical lattice A K Tuchman, W Li, H Chien, S Dettmer and M A Kasevich Quantum switches and quantum memories for matter-wave lattice solitons V Ahufinger, A Mebrahtu, R Corbalán and A Sanpera Quantum noise analysis of spin systems realized with cold atoms Robert W Cherng and Eugene Demler Effective-range description of a Bose gas under strong one- or two-dimensional confinement Pascal Naidon, Eite Tiesinga, William F Mitchell and Paul S Julienne Dissipative dynamics of atomic Hubbard models coupled to a phonon bath: dark state cooling of atoms within a Bloch band of an optical lattice A Griessner, A J Daley, S R Clark, D Jaksch and P Zoller Inhomogeneous broadening of a Mott insulator spectrum V Guarrera, L Fallani, J E Lye, C Fort and M Inguscio Immanuel Bloch, Johannes Gutenberg-Universität, Mainz, Germany Peter Zoller, Universität Innsbruck, Austria

New Journal of PhysicsAug 30, 200616 citations