Dynamics ofF=1Rb87condensates at finite temperatures

Abstract

We investigate the dynamics of a F = 1 spinor Bose-Einstein condensate of 87 Rb atoms confined in a quasi-one-dimensional trap both at zero and at finite temperature. At zero temperature, we observe coherent oscillations between populations of the various spin components and the formation of multiple domains in the condensate. We study also finite temperature effects in the spin dynamics taking into account the phase fluctuations in the Bogoliubov-de Gennes framework. At finite T, despite complex multidomain formation in the condensate, population equipartition occurs. The length scale of these spin domains seems to be determined intrinsically by nonlinear interactions.

Excited spin states and phase separation in spinor Bose-Einstein condensates

“…[8]. The latter constantly appear and disappear in a random sequence [8,14,15,17,34,35]. On the contrary, the ground state domains are stationary and are positioned in the center of the trap.…”

Predicting Spinor Condensate Dynamics from Simple Principles

“…Defining the relative populations m N m =N, the magnetization of the system is M 1 ÿ ÿ1 . The total number of atoms and the magnetization are both conserved quantities [2]. Then, the conditions 1 0 ÿ1…”

“…Even for the simplest case of an F 1 spinor condensate, the interplay between spin-spin interactions, nonlinear terms, and temperature effects rends the analysis of the dynamics rather complex. Previous studies of the spinor dynamics show that, at early stages of the evolution, there is a coherent population transfer between the different hyperfine coupled sublevels [2,3]. Inclusion of temperature (T) not only smears out the population transfer [2], but also leads to a different distribution of population among the different hyperfine levels.…”

“…In the absence of an external magnetic field and at T 0, the properties of the condensate are determined by the spindependent energy functional [2,6,7]:…”

Quantum rotor theory of spinor condensates in tight traps

“…These experiments investigate the dynamics after a quantum quench, which involves the proliferation of topological defects. The second catergory of experiments are performed in tight traps where the spatial degrees of freedom are unimportant [11][12][13][14][15][16][17][18][19]. Such experiments have focused on the coherent spin dynamics after preparing the system in a particular manner.…”