TY - JOUR
T1 - Number Fluctuations and Energy Dissipation in Sodium Spinor Condensates
JF - Physical Review Letters
Y1 - 2009
A1 - Yingmei Liu
A1 - Eduardo Gomez
A1 - Stephen E. Maxwell
A1 - Lincoln D. Turner
A1 - Eite Tiesinga
A1 - Paul D. Lett
AB - We characterize fluctuations in atom number and spin populations in F=1 sodium spinor condensates. We find that the fluctuations enable a quantitative measure of energy dissipation in the condensate. The time evolution of the population fluctuations shows a maximum. We interpret this as evidence of a dissipation-driven separatrix crossing in phase space. For a given initial state, the critical time to the separatrix crossing is found to depend exponentially on the magnetic field and linearly on condensate density. This crossing is confirmed by tracking the energy of the spinor condensate as well as by Faraday rotation spectroscopy. We also introduce a phenomenological model that describes the observed dissipation with a single coefficient.
VL - 102
UR - http://arxiv.org/abs/0906.2110v1
CP - 22
J1 - Phys. Rev. Lett.
U5 - 10.1103/PhysRevLett.102.225301
ER -
TY - JOUR
T1 - Quantum Phase Transitions and Continuous Observation of Spinor Dynamics in an Antiferromagnetic Condensate
JF - Physical Review Letters
Y1 - 2009
A1 - Yingmei Liu
A1 - Sebastian Jung
A1 - Stephen E. Maxwell
A1 - Lincoln D. Turner
A1 - Eite Tiesinga
A1 - Paul. D. Lett
AB - Condensates of spin-1 sodium display rich spin dynamics due to the antiferromagnetic nature of the interactions in this system. We use Faraday rotation spectroscopy to make a continuous and minimally destructive measurement of the dynamics over multiple spin oscillations on a single evolving condensate. This method provides a sharp signature to locate a magnetically tuned separatrix in phase space which depends on the net magnetization. We also observe a phase transition from a two- to a three-component condensate at a low but finite temperature using a Stern-Gerlach imaging technique. This transition should be preserved as a zero-temperature quantum phase transition.
VL - 102
UR - http://arxiv.org/abs/0902.3189v1
CP - 12
J1 - Phys. Rev. Lett.
U5 - 10.1103/PhysRevLett.102.125301
ER -