Manipulation of an elongated internal Josephson junction of bosonic atoms

Stochastic dynamics of a few sodium atoms in presence of a cold potassium cloud

“…Such a setup has been used for the fast creation of Bose-Einstein condensates of sodium, as described in ref. 46 , 49 , 50 .…”

Observation of Massless and Massive Collective Excitations with Faraday Patterns in a Two-Component Superfluid

“…The two-component BEC is prepared by employing the technique described in [21,22], where we coherently transfer half of the atomic population to the |F, m F = |1, 1 state through an adiabatic rapid passage (ARP) sequence. In the presence of a uniform magnetic field B = 1.3 G oriented along the vertical direction, we apply a microwave coupling field that addresses the twophoton transition with an effective Rabi frequency Ω R = 2π × 180 Hz initially red-detuned from the transition to the |1, 1 state.…”

“…The two-component BEC is then prepared through an adiabatic rapid passage (ARP) sequence [21,22], which coherently transfers half of the atomic population to the |1, 1 state, using a two-photon microwave transition [19]. At the end of the ARP, the microwave drive is either completely switched off (experiments in Fig.…”

“…(1-2) with Ω R = 0. Here, the only non-trivial parameter is the BEC peak density n 0 of the 3D distribution, which is independently calibrated by measuring the plasma frequency of the two-component BEC at the center of the cloud [19,22], leading to the estimated chemical potentials, µ d /h = 3 kHz and µ s /h = 145 Hz. In the density channel, the k position of the peak depends linearly on the modulation frequency as k ω M /(2c d ), since all the probed frequencies are well in the sonic region of the dispersion relation, ω M µ d / .…”

“…3(a) and Fig. 4(b)] This originates from a weak coupling between the spin and density modes due to slight imbalance of the density in the two spin states, as well as from some cross-talk between the two spin components in the imaging technique [22].…”