Related papers: Stability of Magnetically Trapped Bose-Einstein Co…
We analyze the stability of non-ground nonlinear states of a Bose-Einstein condensate in the mean field limit in effectively 1D (``cigar-shape'') traps for various types of confining potentials. We find that nonlinear states become, in…
A two-component Bose-Einstein condensate confined in an axially-symmetric potential with two local minima, resembling two concentric annular traps, is investigated. The system shows a number of quantum phase transitions that result from the…
We have produced a Bose-Einstein condensate on a permanent-magnet atom chip based on periodically magnetized videotape. We observe the expansion and dynamics of the condensate in one of the microscopic waveguides close to the surface. The…
We have investigated the properties of Bose-Einstein condensates of sodium atoms in the upper hyperfine ground state in a purely optical trap. Condensates in the high-field seeking $| F=2, m_F=-2>$ state were created from initially prepared…
We demonstrate that atoms in magnetically insensitive hyperfine states (m=0) can be trapped efficiently by a Bose-Einstein Condensate of the same atomic species occupying a different hyperfine state. The latter is trapped magnetically.…
We study the dynamics of two-component Bose-Einstein condensates trapped in different vertical positions in the presence of an oscillating magnetic field. It is shown here how tuning appropriately the oscillation frequency of the magnetic…
We consider a large condensate in a rotating anisotropic harmonic trap. Using the method of matched asymptotic expansions, we derive the velocity of an element of vortex line as a function of the local gradient of the trap potential, the…
The dynamical behavior of Bose-Einstein condensation (BEC) in a gas with attractive interactions is striking. Quantum theory predicts that BEC of a spatially homogeneous gas with attractive interactions is precluded by a conventional phase…
Current magnetic traps can be made so anisotropic that the atomic gas trapped inside behaves like quasi one or two dimensional system. Unlike the homogeneous case, quantum phase fluctuations do not destroy macroscopic off-diagonal order of…
Recent experiments with trapped cooled atoms have produced evidences for Bose-Einstein condensation. Among the atoms used are $^7Li$ ones, with attractive low energy interaction. Stability of their condensate is studied, with a conclusion…
We study, by means of a variational method, the stability of a condensate in a magnetically trapped atomic Bose gas with a negative scattering length and find that the condensate is unstable in general. However, for temperatures…
A Bose-Einstein condensate is created in a simple and robust miniature Ioffe-Pritchard trap, the so-called Z trap. This trap follows from the mere combination of a Z-shaped current carrying wire and a homogeneous bias field. The…
Three hyperfine states of Bose-condensed sodium atoms, recently optically trapped, can be described as a spin-1 Bose gas. We study the behaviour of this system in a magnetic field, and construct the phase diagram, where the temperature of…
We analyze, analytically and numerically, the position, momentum, and in particular the angular-momentum variance of a Bose-Einstein condensate (BEC) trapped in a two-dimensional anisotropic trap for static and dynamic scenarios. The…
We consider Bose-Einstein condensed atoms confined in a toroidal trap. We demonstrate that under conditions of one-dimensional behavior, the density distribution of the atoms may be exponentially localized/delocalized, even for very small…
We study theoretically Bose-Einstein condensates with polarized dipolar interactions in anisotropic traps. We map the parameter space by varying the trap frequencies and dipolar interaction strengths and find an irregular-shaped region of…
We show that the stability of three-dimensional Skyrmions in trapped Bose-Einstein condensates depends critically on scattering lengths, atom numbers, trap rotation and trap anisotropy. In particular, for the $^{87}$Rb $|F=1,m_{f}=-1>$,…
We describe a self-biased, fully permanent magnet atom chip used to study ultracold atoms and to produce a Bose-Einstein condensate (BEC). The magnetic trap is loaded efficiently by adiabatic transport of a magnetic trap via the application…
We analyze the decay of ultracold atoms from an optical lattice with loss form a single lattice site. If the initial state is dynamically stable a suitable amount of dissipation can stabilize a Bose-Einstein condensate, such that it remains…
The dynamics of a coupled Bose-Einstein condensate involving trapped atoms in two quantum states is studied using the time-dependent Gross-Pitaevskii equation including an interaction which can transform atoms from one state to the other.…