Dynamics of two colliding Bose condensate in a magnetostatic trap

We experimentally and theoretically investigate the dynamics of two trapped condensates in a magnetostatic trap. The two condensates, being in different internal Zeeman state (|F=2,m=2〉 and |F=2,m=1〉), experience external parabolic potentials that differ by both curvature and equilibrium position.The dynamics of the system, exhibiting large amplitude oscillations of the |F=2,m=1〉 condensate, is affected in a profound manner by the periodical intercondensates collisions.In particular, we show that both an amplitude damping and a frequency shift occur. Measuring the former allows to study the elastic scattering, whose suppression is a manifestation of the Bose condensates superfluidity, while the latter gives access to the cross scattering length a21.We experimentally and theoretically investigate the dynamics of two trapped condensates in a magnetostatic trap. The two condensates, being in different internal Zeeman state (|F=2,m=2〉 and |F=2,m=1〉), experience external parabolic potentials that differ by both curvature and equilibrium position.The dynamics of the system, exhibiting large amplitude oscillations of the |F=2,m=1〉 condensate, is affected in a profound manner by the periodical intercondensates collisions.In particular, we show that both an amplitude damping and a frequency shift occur. Measuring the former allows to study the elastic scattering, whose suppression is a manifestation of the Bose condensates superfluidity, while the latter gives access to the cross scattering length a21.

AIP conference proceedingsJan 1, 20010 citations

Damping and frequency shift in the oscillations of two colliding Bose-Einstein condensates

Michele Modugno, C. Fort, INGUSCIO, MASSIMO +2 more

We have investigated the center-of-mass oscillations of a Rb87 Bose-Einstein condensate in an elongated magneto-static trap. We start from a trapped condensate and we transfer part of the atoms to another trapped level, by applying a radio-frequency pulse. The new condensate is produced far from its equilibrium position in the magnetic potential, and periodically collides with the parent condensate. We discuss how both the damping and the frequency shift of the oscillations are affected by the mutual interaction between the two condensates, in a wide range of trapping frequencies. The experimental data are compared with the prediction of a mean-field model.We have investigated the center-of-mass oscillations of a Rb87 Bose-Einstein condensate in an elongated magneto-static trap. We start from a trapped condensate and we transfer part of the atoms to another trapped level, by applying a radio-frequency pulse. The new condensate is produced far from its equilibrium position in the magnetic potential, and periodically collides with the parent condensate. We discuss how both the damping and the frequency shift of the oscillations are affected by the mutual interaction between the two condensates, in a wide range of trapping frequencies. The experimental data are compared with the prediction of a mean-field model.

Jan 1, 20011 citation

Dynamics of two colliding Bose-Einstein condensates in an elongated magnetostatic trap

Michele Modugno, F. Dalfovo, C. Fort +2 more

We study the dynamics of two interacting Bose-Einstein condensates, by numerically solving two coupled Gross-Pitaevskii equations at zero temperature. We consider the case of a sudden transfer of atoms between two trapped states with different magnetic moments: the two condensates are initially created with the same density profile, but are trapped into different magnetic potentials, whose minima are vertically displaced by a distance much larger than the initial size of both condensates. Then the two condensates begin to perform collective oscillations, undergoing a complex evolution, characterized by collisions between the two condensates. We investigate the effects of their mutual interaction on the center-of-mass oscillations and on the time evolution of the aspect ratios. Our theoretical analysis provides a useful insight into the recent experimental observations by Maddaloni et al. [Phys. Rev. Lett. 85, 2413 (2000)].We study the dynamics of two interacting Bose-Einstein condensates, by numerically solving two coupled Gross-Pitaevskii equations at zero temperature. We consider the case of a sudden transfer of atoms between two trapped states with different magnetic moments: the two condensates are initially created with the same density profile, but are trapped into different magnetic potentials, whose minima are vertically displaced by a distance much larger than the initial size of both condensates. Then the two condensates begin to perform collective oscillations, undergoing a complex evolution, characterized by collisions between the two condensates. We investigate the effects of their mutual interaction on the center-of-mass oscillations and on the time evolution of the aspect ratios. Our theoretical analysis provides a useful insight into the recent experimental observations by Maddaloni et al. [Phys. Rev. Lett. 85, 2413 (2000)].

arXiv:cond-mat/0007091Physical Review ANov 14, 200039 citations

Suppression of elastic scattering loss for slowly colliding Bose-Einstein condensates

Y. B. Band, John H. Burke, Andrea Simoni +1 more

Superfluid suppression of the elastic scattering loss in atomic Bose condensed systems can be significant when the ratio of the relative velocity of the wave packets to the critical velocity is $\ensuremath{\sim}1.$ We show how to incorporate the effect of such losses and their suppression into the time-dependent dynamics of two colliding condensate wave packets. We illustrate the magnitude of the effect through three-dimensional simulations of the collision dynamics of an $|F=2,{M}_{F}=2〉$ with an $|F=2,{M}_{F}=1〉{}^{87}\mathrm{Rb}$ condensate in a harmonic trap, as studied in a recent experiment [Maddaloni et al., Phys. Rev. Lett. 85, 2413 (2000)]. These calculations show that the effect of elastic scattering and its suppression should be seen in the oscillatory center-of-mass amplitude of the ${M}_{F}=1$ wave packet for suitable experimental conditions.Superfluid suppression of the elastic scattering loss in atomic Bose condensed systems can be significant when the ratio of the relative velocity of the wave packets to the critical velocity is $\ensuremath{\sim}1.$ We show how to incorporate the effect of such losses and their suppression into the time-dependent dynamics of two colliding condensate wave packets. We illustrate the magnitude of the effect through three-dimensional simulations of the collision dynamics of an $|F=2,{M}_{F}=2〉$ with an $|F=2,{M}_{F}=1〉{}^{87}\mathrm{Rb}$ condensate in a harmonic trap, as studied in a recent experiment [Maddaloni et al., Phys. Rev. Lett. 85, 2413 (2000)]. These calculations show that the effect of elastic scattering and its suppression should be seen in the oscillatory center-of-mass amplitude of the ${M}_{F}=1$ wave packet for suitable experimental conditions.

Physical Review AJul 1, 200111 citations

Dynamics of a coupled spin-vortex pair in dipolar spinor Bose-Einstein condensates

Tiantian Li, Su Yi, Yunbo Zhang

The collisional and magnetic field quench dynamics of a coupled spin-vortex pair in dipolar spinor Bose-Einstein condensates in a double-well potential are numerically investigated in the mean-field theory. Upon a sudden release of the potential barrier the two layers of condensates collide with each other in the trap center with the chirality of the vortex pair exchanged after each collision, showing the typical signature of in-phase collision for the parallel spin-vortex phase, and out-of-phase collision for the antiparallel phase. When quenching the transverse magnetic field, the vortex center in the single-layered condensate starts to make a helical motion with oval-shaped trajectories and the displacement of the center position is found to exhibit a damped simple harmonic oscillation with an intrinsic frequency and damping rate. The oscillation mode of the spin-vortex pair may be tuned by the initial magnetic field and the height of the Gaussian barrier; e.g., the gyrotropic motions for a parallel spin-vortex pair are out of sync with each other in the two layers, while those for the antiparallel pair exhibit a double-helix structure with the vortex centers moving opposite to each other with the same amplitude.The collisional and magnetic field quench dynamics of a coupled spin-vortex pair in dipolar spinor Bose-Einstein condensates in a double-well potential are numerically investigated in the mean-field theory. Upon a sudden release of the potential barrier the two layers of condensates collide with each other in the trap center with the chirality of the vortex pair exchanged after each collision, showing the typical signature of in-phase collision for the parallel spin-vortex phase, and out-of-phase collision for the antiparallel phase. When quenching the transverse magnetic field, the vortex center in the single-layered condensate starts to make a helical motion with oval-shaped trajectories and the displacement of the center position is found to exhibit a damped simple harmonic oscillation with an intrinsic frequency and damping rate. The oscillation mode of the spin-vortex pair may be tuned by the initial magnetic field and the height of the Gaussian barrier; e.g., the gyrotropic motions for a parallel spin-vortex pair are out of sync with each other in the two layers, while those for the antiparallel pair exhibit a double-helix structure with the vortex centers moving opposite to each other with the same amplitude.

arXiv:1607.03983Physical Review AMay 4, 201610 citations

Collective Oscillations of Two Colliding Bose-Einstein Condensates

P. Maddaloni, Michele Modugno, C. Fort +2 more

Two ${}^{87}\mathrm{Rb}$ condensates ( $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$ , ${m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$ , and ${m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$ ) are produced in highly displaced harmonic traps and the collective dynamical behavior is investigated. The mutual interaction between the two condensates is evidenced in the center-of-mass oscillations as a frequency shift of $6.4(3)%$ . Calculations based on a mean-field theory well describe the observed effects of periodical collisions both on the center-of-mass motion and on the shape oscillations.Two ${}^{87}\mathrm{Rb}$ condensates ( $F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$, ${m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$, and ${m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$) are produced in highly displaced harmonic traps and the collective dynamical behavior is investigated. The mutual interaction between the two condensates is evidenced in the center-of-mass oscillations as a frequency shift of $6.4(3)%$. Calculations based on a mean-field theory well describe the observed effects of periodical collisions both on the center-of-mass motion and on the shape oscillations.

arXiv:cond-mat/0003402Physical Review LettersSep 18, 2000152 citations

|F=2,{M}_{F}=2〉

with an

|F=2,{M}_{F}=1〉{}^{87}\mathrm{Rb}

condensate in a harmonic trap, as studied in a recent experiment [Maddaloni et al., Phys. Rev. Lett. 85, 2413 (2000)]. These calculations show that the effect of elastic scattering and its suppression should be seen in the oscillatory center-of-mass amplitude of the

{M}_{F}=1

wave packet for suitable experimental conditions.

Two

{}^{87}\mathrm{Rb}

condensates (

F\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2

{m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2

, and

{m}_{f}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1

) are produced in highly displaced harmonic traps and the collective dynamical behavior is investigated. The mutual interaction between the two condensates is evidenced in the center-of-mass oscillations as a frequency shift of

6.4(3)%

. Calculations based on a mean-field theory well describe the observed effects of periodical collisions both on the center-of-mass motion and on the shape oscillations.