arXiv:1212.5004 · Physical Review A

Dipolar droplet bound in a trapped Bose-Einstein condensate

Luis E. Young-S., Sadhan K. Adhikari

Published Jan 17, 2013• 13 citations

Abstract

We study the statics and dynamics of a dipolar Bose-Einstein condensate (BEC) droplet bound by interspecies contact interaction in a trapped nondipolar BEC. Our findings are demonstrated in terms of stability plots of a dipolar ${}^{164}$Dy droplet bound in a trapped nondipolar ${}^{87}$Rb BEC with a variable number of ${}^{164}$Dy atoms and interspecies scattering length. A trapped nondipolar BEC of a fixed number of atoms can bind only a dipolar droplet containing fewer atoms than a critical number for the interspecies scattering length between two critical values. The shape and size (statics) as well as the small breathing oscillation (dynamics) of the dipolar BEC droplet are studied using numerical and variational solutions of a mean-field model. We also suggest an experimental procedure for achieving such a ${}^{164}$Dy droplet by relaxing the trap on the ${}^{164}$Dy BEC in a trapped binary ${}^{87}$Rb-${}^{164}$Dy mixture.

DOI: 10.1103/physreva.87.013618

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arXiv:1212.5004 · Physical Review A

Dipolar droplet bound in a trapped Bose-Einstein condensate

Luis E. Young-S., Sadhan K. Adhikari

Published Jan 17, 2013• 13 citations

arXiv HTML PDF

Abstract

{}^{164}

Dy droplet bound in a trapped nondipolar

{}^{87}

Rb BEC with a variable number of

{}^{164}

Dy atoms and interspecies scattering length. A trapped nondipolar BEC of a fixed number of atoms can bind only a dipolar droplet containing fewer atoms than a critical number for the interspecies scattering length between two critical values. The shape and size (statics) as well as the small breathing oscillation (dynamics) of the dipolar BEC droplet are studied using numerical and variational solutions of a mean-field model. We also suggest an experimental procedure for achieving such a

{}^{164}

Dy droplet by relaxing the trap on the

{}^{164}

Dy BEC in a trapped binary

{}^{87}

Rb-

{}^{164}

Dy mixture.

DOI: 10.1103/physreva.87.013618

Related papers

Statics and dynamics of a binary dipolar Bose–Einstein condensate soliton

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We study the statics and dynamics of a binary dipolar Bose–Einstein condensate soliton for repulsive inter and intraspecies contact interactions with the two components subject to different spatial symmetries—distinct quasi-one-dimensional and quasi-two-dimensional shapes—using numerical solution and variational approximation of a three-dimensional mean-field model. The results are illustrated with realistic values of parameters in the binary 164 Dy- 168 Er mixture. The possibility of forming robust dipolar solitons of a very large number of atoms make them of great experimental interest. The existence of the solitons is illustrated in terms of stability phase diagrams. Exotic shapes of these solitons are illustrated in isodensity plots. The variational results for statics (size and chemical potential) and dynamics (small oscillation) of the binary soliton compare well with the numerical results. A way of preparing and studying these solitons in the laboratory is suggested.We study the statics and dynamics of a binary dipolar Bose–Einstein condensate soliton for repulsive inter and intraspecies contact interactions with the two components subject to different spatial symmetries—distinct quasi-one-dimensional and quasi-two-dimensional shapes—using numerical solution and variational approximation of a three-dimensional mean-field model. The results are illustrated with realistic values of parameters in the binary 164 Dy- 168 Er mixture. The possibility of forming robust dipolar solitons of a very large number of atoms make them of great experimental interest. The existence of the solitons is illustrated in terms of stability phase diagrams. Exotic shapes of these solitons are illustrated in isodensity plots. The variational results for statics (size and chemical potential) and dynamics (small oscillation) of the binary soliton compare well with the numerical results. A way of preparing and studying these solitons in the laboratory is suggested.

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Sadhan K. Adhikari

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Aug 18, 20164 citations

{}^{164}

Dy droplet bound in a trapped nondipolar

{}^{87}

Rb BEC with a variable number of

{}^{164}

{}^{164}

Dy droplet by relaxing the trap on the

{}^{164}

Dy BEC in a trapped binary

{}^{87}

Rb-

{}^{164}

Dy mixture.

We study the static properties of disk-shaped binary dipolar Bose-Einstein condensates of

{}^{168}

Er-

{}^{164}

Dy and

{}^{52}

Cr-

{}^{164}

Dy mixtures under the action of interspecies and intraspecies contact and dipolar interactions and demonstrate the effect of dipolar interaction using the mean-field approach. Throughout this study we use realistic values of interspecis and intraspecies dipolar interactions and the intraspecies scattering lengths and consider the interspecies scattering length as a parameter. The stability of the binary mixture is illustrated through phase plots involving a number of atoms of the species. The binary system always becomes unstable as the number of atoms increases beyond a certain limit. As the interspecies scattering length increases corresponding to more repulsion, an overlapping mixed state of the two species changes to a separated demixed configuration. During the transition from a mixed to a demixed configuration as the interspecies scattering length is increased for parameters near the stability line, the binary condensate shows special transient structures in density in the form of red-blood-cell-like biconcave and Saturn-ring-like shapes, which are direct manifestations of the dipolar interaction.