Phases of a 2D Bose Gas in an Optical Lattice

Abstract

Ultra-cold atoms in optical lattices realize simple, fundamental models in condensed matter physics. Our 87Rb Bose-Einstein condensate is confined in a harmonic trapping potential to which we add an optical lattice potential. Here we realize the 2D Bose-Hubbard Hamiltonian and focus on the effects of the harmonic trap, not present in bulk condensed matter systems. By measuring condensate fraction we identify the transition from superfluid to Mott insulator as a function of atom density and lattice depth. Our results are in excellent agreement with the quantum Monte Carlo universal state diagram, suitable for trapped systems, introduced by Rigol et al. (Phys. Rev. A 79, 053605 (2009)).

5 pages, 4 figures

References in corpus (6)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Imaging the Mott Insulator Shells using Atomic Clock Shifts
• Quantum Monte Carlo simulations of confined bosonic atoms in optical lattices
• Formation of spatial shell structures in the superfluid to Mott insulator transition
• Phase diagram for a Bose-Einstein condensate moving in an optical lattice
• Condensate fraction in a 2D Bose gas measured across the Mott-insulator transition

Cited by in corpus (16)

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• Clock spectroscopy of interacting bosons in deep optical lattices
• Quantum Criticality from in-situ Density Imaging
• Effect of particle statistics in strongly correlated two-dimensional Hubbard models
• Polarons and bipolarons in a two-dimensional square lattice
• Controlling coherence via tuning of the population imbalance in a bipartite optical lattice
• Oscillatory pairing of fermions in spin-split traps
• Scaling behaviour of trapped bosonic particles in two dimensions at finite temperature
• Critical points of the three-dimensional Bose-Hubbard model from on-site atom number fluctuations
• Non-local correlation and entanglement of ultracold bosons in the two-dimensional Bose-Hubbard lattice at finite temperature
• Studying the low-entropy Mott transition of bosons in a three-dimensional optical lattice by measuring the full momentum-space density
• Staggered quantum phases of dipolar bosons at finite temperatures
• Strong-coupling RPA theory of a Bose gas near the superfluid--Mott-insulator transition: universal thermodynamics and two-body contact
• Excitation Spectra and Hard-core Thermodynamics of Bosonic Atoms In Double Well Optical Lattices