Classical and quantum filaments in the ground state of trapped dipolar Bose gases
CITATION: Cinti, F. & Boninsegni, M. 2017. Classical and quantum filaments in the ground state of trapped dipolar Bose gases. Physical Review A, 96(1):013627, doi:10.1103/PhysRevA.96.013627.
The original publication is available at http://journals.aps.org/pra
We study, by quantum Monte Carlo simulations, the ground state of a harmonically confined dipolar Bose gas with aligned dipole moments and with the inclusion of a repulsive two-body potential of varying range. Two different limits can clearly be identified, namely, a classical one in which the attractive part of the dipolar interaction dominates and the system forms an ordered array of parallel filaments and a quantum-mechanical one, wherein filaments are destabilized by zero-point motion, and eventually the ground state becomes a uniform cloud. The physical character of the system smoothly evolves from classical to quantum mechanical as the range of the repulsive two-body potential increases. An intermediate regime is observed in which ordered filaments are still present, albeit forming different structures from the ones predicted classically; quantum-mechanical exchanges of indistinguishable particles across different filaments allow phase coherence to be established, underlying a global superfluid response.