Off-diagonal correlations in a one-dimensional gas of dipolar bosons

Abstract

We present a quantum Monte Carlo study of the one-body density matrix (OBDM) and the momentum distribution of one-dimensional dipolar bosons, with dipole moments polarized perpendicular to the direction of confinement. We observe that the long-range nature of the dipole interaction has dramatic effects on the off-diagonal correlations: although the dipoles never crystallize, the system goes from a quasi-condensate regime at low interactions to a regime in which quasi-condensation is discarded, in favor of quasi-solidity. For all strengths of the dipolar interaction, the OBDM shows an oscillatory behavior coexisting with an overall algebraic decay; and the momentum distribution shows sharp kinks at the wavevectors of the oscillations, $Q=\pm 2\pi n$ (where $n$ is the atom density), beyond which it is strongly suppressed. This \emph{momentum filtering} effect introduces a characteristic scale in the momentum distribution, which can be arbitrarily squeezed by lowering the atom density. This shows that one-dimensional dipolar Bose gases, realized e.g. by trapped dipolar molecules, show strong signatures of the dipolar interaction in time-of-flight measurements.

10 pages, 6 figures. v2: fixed a mistake in the comparison with Ref. 9, as well as several typos. Published version

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Cited by in corpus (11)

• Condensed Matter Theory of Dipolar Quantum Gases
• 1D Quantum Liquids with Power-Law Interactions: a Luttinger Staircase with Polar Molecules
• Estimating Quasi-long-range Order via Renyi Entropies
• Bosonic and fermionic dipoles on a ring
• Lieb-Liniger model with exponentially-decaying interactions: a continuous matrix product state study
• Supersolid phases of bosonic particles in a bubble trap
• Dipolar bosons on an optical lattice ring
• Variational Bethe Ansatz approach for dipolar one-dimensional bosons
• Spontaneous Peierls dimerization and emergent bond order in one-dimensional dipolar gases
• Polarization angle dependence of the breathing modes in confined one-dimensional dipolar bosons
• Dipolar bosons in one dimension: the case of longitudinal dipole alignment