Communications in Theoretical Physics ›› 2020, Vol. 72 ›› Issue (8): 085501. doi: 10.1088/1572-9494/ab95fa

• Atomic, Molecular, Optical (AMO) and Plasma Physics, Chemical Physics • Previous Articles     Next Articles

Variational theory for the ground state and collective excitations of an elongated dipolar condensate

P Blair Blakie(),D Baillie,Sukla Pal   

  1. Dodd-Walls Centre for Photonic and Quantum Technologies, New Zealand and Department of Physics, University of Otago, Dunedin 9016, New Zealand
  • Received: 2020-02-21 Revised: 2020-04-21 Accepted: 2020-05-15 Published: 2020-08-01


We develop a variational theory for a dipolar condensate in an elongated (cigar shaped) confinement potential. Our formulation provides an effective one-dimensional extended meanfield theory for the ground state and its collective excitations. We apply our theory to investigate the properties of rotons in the system comparing the variational treatment to a full numerical solution. We consider the effect of quantum fluctuations on the scattering length at which the roton excitation softens to zero energy.

Key words: dipolar Bose–Einstein condensate, ground states, collective excitations