We perform detailed close-coupling calculations for the rubidium isotopes ${}^{85}\mathrm{Rb}$ and ${}^{87}\mathrm{Rb}$ to ascertain the nature of their spinor Bose-Einstein condensates. These calculations predict that the spinor condensate for the spin-1 boson ${}^{87}\mathrm{Rb}$ has a ferromagnetic nature. The spinor condensates for the spin-2 bosons ${}^{85}\mathrm{Rb}$ and ${}^{87}\mathrm{Rb},$ however, are both predicted to be polar. The nature of a spin-1 condensate hinges critically on the sign of the difference between the s-wave scattering lengths for total spins 0 and 2 while the nature of a spin-2 condensate depends on the values of the differences between s-wave scattering lengths for the total spins 0, 2, and 4. These scattering lengths were extracted previously and found to have overlapping uncertainties for all three cases, thus leaving the nature of the spinor condensates ambiguous. The present study exploits a refined uncertainty analysis of the scattering lengths based on recently improved result from experimental work by Roberts et al., which permits us to extract an unambiguous result for the nature of the ground state spinor condensates.We perform detailed close-coupling calculations for the rubidium isotopes ${}^{85}\mathrm{Rb}$ and ${}^{87}\mathrm{Rb}$ to ascertain the nature of their spinor Bose-Einstein condensates. These calculations predict that the spinor condensate for the spin-1 boson ${}^{87}\mathrm{Rb}$ has a ferromagnetic nature. The spinor condensates for the spin-2 bosons ${}^{85}\mathrm{Rb}$ and ${}^{87}\mathrm{Rb},$ however, are both predicted to be polar. The nature of a spin-1 condensate hinges critically on the sign of the difference between the s-wave scattering lengths for total spins 0 and 2 while the nature of a spin-2 condensate depends on the values of the differences between s-wave scattering lengths for the total spins 0, 2, and 4. These scattering lengths were extracted previously and found to have overlapping uncertainties for all three cases, thus leaving the nature of the spinor condensates ambiguous. The present study exploits a refined uncertainty analysis of the scattering lengths based on recently improved result from experimental work by Roberts et al., which permits us to extract an unambiguous result for the nature of the ground state spinor condensates.

arXiv:physics/0104013Physical Review AOct 2, 2001166 citations

Elementary excitations of spinor Bose-Einstein condensates

Wai-ho Tang

Jan 1, 20160 citations

Collisions at nanokelvin temperatures in Bose-Einstein condensates

Wolfgang Ketterle

Bose-Einstein condensed atomic gases are a new class of quantum fluids. They are produced by cooling a dilute atomic gas to nanokelvin temperatures using laser and evaporative cooling techniques. In this paper we review developments in Bose-Einstein condensation, emphasizing how this new quantum fluid has become a laboratory for the study of collisions at ultralow energy and of collective effects in light-atom and atom-atom interactions. Magnetic fields have been used to modify the scattering length for atomic collisions. Spinor condensates were created, with a spin structure determined by spin relaxation collisions and external magnetic fields. We have used light scattering to study collective excitations and observed superradiant light emission. Dissipation was studied by dragging a repulsive, blue-detuned laser beam through the fluid, as well as by inducing collisions between condensates.Bose-Einstein condensed atomic gases are a new class of quantum fluids. They are produced by cooling a dilute atomic gas to nanokelvin temperatures using laser and evaporative cooling techniques. In this paper we review developments in Bose-Einstein condensation, emphasizing how this new quantum fluid has become a laboratory for the study of collisions at ultralow energy and of collective effects in light-atom and atom-atom interactions. Magnetic fields have been used to modify the scattering length for atomic collisions. Spinor condensates were created, with a spin structure determined by spin relaxation collisions and external magnetic fields. We have used light scattering to study collective excitations and observed superradiant light emission. Dissipation was studied by dragging a repulsive, blue-detuned laser beam through the fluid, as well as by inducing collisions between condensates.

AIP conference proceedingsJan 1, 20000 citations

Scattering from a Bose-Einstein Condensate

S. Inouye, A. P. Chikkatur, Dan Stamper-Kurn +3 more

Jan 1, 19990 citations

We perform detailed close-coupling calculations for the rubidium isotopes

{}^{85}\mathrm{Rb}

and

{}^{87}\mathrm{Rb}

to ascertain the nature of their spinor Bose-Einstein condensates. These calculations predict that the spinor condensate for the spin-1 boson

{}^{87}\mathrm{Rb}

has a ferromagnetic nature. The spinor condensates for the spin-2 bosons

{}^{85}\mathrm{Rb}

and

{}^{87}\mathrm{Rb},

however, are both predicted to be polar. The nature of a spin-1 condensate hinges critically on the sign of the difference between the s-wave scattering lengths for total spins 0 and 2 while the nature of a spin-2 condensate depends on the values of the differences between s-wave scattering lengths for the total spins 0, 2, and 4. These scattering lengths were extracted previously and found to have overlapping uncertainties for all three cases, thus leaving the nature of the spinor condensates ambiguous. The present study exploits a refined uncertainty analysis of the scattering lengths based on recently improved result from experimental work by Roberts et al., which permits us to extract an unambiguous result for the nature of the ground state spinor condensates.