相关论文: An acoustic probe for quantum vorticity in Bose-Ei…
In the present Master's thesis, I describe the research I conducted during my Master's program on the topic of analogue gravity. This line of research was initiated by Bill Unruh, who established an analogy between hydrodynamic flow with a…
We measure the axial momentum distribution of Bose-Einstein condensates with an aspect ratio of 152 using Bragg spectroscopy. We observe the Lorentzian momentum distribution characteristic of one-dimensional phase fluctuations. The…
The decay of multicharged vortices in trapped Bose-Einstein condensates may lead to a disordered vortex state consistent with the Vinen regime of turbulence, characterized by an absence of large-scale flow and an incompressible kinetic…
We observe interlaced square vortex lattices in rotating two-component dilute-gas Bose-Einstein condensates (BEC). After preparing a hexagonal vortex lattice in a single-component BEC in an internal state $|1>$ of $^{87}$Rb atoms, we…
Weakly interacting, dilute atomic Bose-Einstein condensates (BECs) have proved to be an attractive context for the study of nonlinear dynamics and quantum effects at the macroscopic scale. Recently, atomic BECs have been used to investigate…
We derive, from the Gross-Pitaevskii equation, an exact expression for the velocity of any vortex in a Bose-Einstein condensate, in equilibrium or not, in terms of the condensate wave function at the center of the vortex. In general, the…
We suggest a method to create turbulence in a trapped atomic Bose-Einstein condensate (BEC). By replacing in the upper half part of our box the wave function, Psi, with its complex conjugate, Psi^{*}, new negative vortices are introduced…
With use of the nonlinear Schr{\"o}dinger (or Gross-Pitaevskii) equation with strong repulsive cubic nonlinearity, dynamics of multi-component Bose-Einstein condensates (BECs) with a harmonic trap in 2 dimensions is investigated beyond the…
When vortices are displaced in Bose-Einstein condensates (BEC), the Magnus force gives the system a momentum transverse in the direction to the displacement. We show that Bose-Einstein condensates (BEC) in long channels with vortices…
The expansion of Bose-Einstein condensates (BECs) is numerically studied. Usually, the aspect ratio of a condensate is inverted due to the anisotropy of the uncertainty principle. In turbulent BECs, however, the aspect ratio remains…
We study the phase transitions in a one dimensional Bose-Einstein condensate on a ring whose atomic scattering length is modulated periodically along the ring. By using a modified Bogoliubov method to treat such a nonlinear lattice in the…
Applications of non-Riemannian acoustic geometries in Bose-Einstein condensates (BEC) are considered. The first is the Minkowski-Cartan irrotational vortex acoustic geometry of nonlinear Schr\"{o}dinger equations of BEC (Gross-Pitaeviskii…
We analyse the rotation of bright solitary waves formed of atomic Bose-Einstein condensates with attractive atomic interactions. By employing a variational technique and assuming an irrotational quadrupolar flow field, we map out the…
The similarity between matter waves in periodic potential and solid-state physics processes has triggered the interest in quantum simulation using Bose-Fermi ultracold gases in optical lattices. The present work evidences the similarity…
We investigate wave-vortex interaction emerging from an expanding compact vortex cluster in a two-dimensional Bose-Einstein condensate. We adapt techniques developed for compact gravitational objects to derive the characteristic modes of…
We investigate the vortex lattices of harmonically confined quasi-two-dimensional tilted rotational dipolar Bose-Einstein condensates. By employing an extended Gross-Pitaevskii equation for a rotating condensate, we reveal the structural…
The dynamical vortex production, with a trap-confining time-dependent stirred potential, is studied by using mass-imbalanced cold-atom coupled Bose-Einstein condensates (BEC). The vortex formation is explored by considering that both…
We consider a Bose-Einstein condensate confined in a ``Mexican hat'' potential, with a quartic minus quadratic radial dependence. We find conditions under which the ground state is annular in shape, with a hole in the center of the…
The final stage of Bose-Einstein condensation in a large volume occurs through coarsening--growth of individual correlated patches. We present analytical arguments and numerical evidence that in the momentum space this growth corresponds to…
We report the results of an experimental study of an analog of the Aharonov-Bohm (AB) effect achieved with the hydrodynamic pilot-wave system. A walking droplet is confined to an annular cavity that encircles a shielded vortex, but lies…