Comment on "Feshbach-Einstein Condensates" by V. G. Rousseau and P. J. H. Denteneer

Abstract

In a recent paper (Phys. Rev. Lett. 102, 015301 (2009), arXiv:0810.3763) Rousseau and Denteneer claim that an unconventional "super-Mott" (SM) phase is realized by bosons trapped in an optical lattice close to a Feshbach resonance with a molecular state. The supposed SM phase, observed via quantum Monte Carlo (QMC) simulations of an atom-molecule Bose-Hubbard model, is an incompressible phase developing spontaneous atomic/molecular supercurrents which are perfectly anticorrelated. Here we show that the identification of this phase is based on a misinterpretation of the estimators of superfluidity in QMC, which break down in the presence of coherent atom/molecule conversion. Our conclusion is that the supposed SM phase is in fact a fully normal insulator.

arXiv comment1+epsilon page, 1 figure

References in corpus (5)

• Counterflow Superfluidity of Two-Species Ultracold Atoms in a Commensurate Optical Lattice
• Quantum Monte Carlo study of S=1/2 weakly-anisotropic antiferromagnets on the square lattice
• Feshbach-Einstein condensates
• Quantum phases of mixtures of atoms and molecules on optical lattices
• Feshbach Resonance in Optical Lattices and the Quantum Ising Model

Cited by in corpus (13)

• Ultracold bosons with short-range interaction in regular optical lattices
• Ising Deconfinement Transition Between Feshbach-Resonant Superfluids
• Discrete Symmetry Breaking Transitions Between Paired Superfluids
• Thermal Phase transitions in attractive extended Bose-Hubbard Model with three-body constraint
• The superfluid density in continuous and discrete spaces: Avoiding misconceptions
• Ground state phase diagram of spin-1/2 bosons in a two-dimensional optical lattice
• Feshbach-Stabilized Insulator of Bosons in Optical Lattices
• Multiple Transitions of Coupled Atom-Molecule Bosonic Mixtures in Two Dimensions
• Properties of the single-site reduced density matrix in the Bose-Bose resonance model in the ground state and in quantum quenches
• Finite temperature phase diagram of spin-1/2 bosons in two-dimensional optical lattice
• Quantum and Thermal Phase Transitions in a Bosonic Atom-Molecule Mixture in a Two-dimensional Optical Lattice
• Magnetic Properties of the Second Mott Lobe in Pairing Hamiltonians
• Competing exotic quantum phases of spin-$1/2$ ultra-cold lattice bosons with extended spin interactions