Dipolar Bose–Einstein condensation of ¹⁶⁸Er and anisotropic expansion dynamics

We report on the realization of Bose–Einstein condensation (BEC) of ¹⁶⁸Er atoms in a crossed optical dipole trap. A magneto-optical trap is realized with just one laser driving the narrow-line transition which increases the phase space density and facilitates the evaporative cooling. A pure BEC with 3 × 10⁴ atoms is achieved by forced evaporative cooling. The complex Feshbach resonance and anisotropic expansion of ¹⁶⁸Er are investigated by the loss spectroscopy and controlling the rotating dipoles.