Spin-Dipole Oscillation and Polarizability of a Binary Bose-Einstein Condensate near the Miscible-Immiscible Phase Transition

TL;DR

This study measures the spin-dipole polarizability and oscillation frequency in a sodium Bose-Einstein condensate, revealing significant enhancement near the miscible-immiscible phase transition, and compares results with theoretical predictions.

Contribution

It provides the first experimental measurement of spin-dipole polarizability and oscillation frequency in a binary BEC near the phase transition, confirming theoretical models.

Findings

Large enhancement of SD polarizability near transition

Softening of SD oscillation frequency close to phase change

Experimental results agree with theoretical predictions

Abstract

We report on the measurement of the spin-dipole (SD) polarizability and of the frequency of the SD oscillation of a two-component Bose-Einstein condensate of sodium atoms occupying the $|3^2S_{1/2}, F=1, m_F=\pm1\rangle$ hyperfine states. This binary spin-mixture presents the important properties of being, at the same time, fully miscible and rid of the limit set by buoyancy. It is also characterized by a huge enhancement of the SD polarizability and by the consequent softening of the frequency of the SD oscillation, due to the vicinity to the transition to the immiscible phase. The experimental data are successfully compared with the predictions of theory.