Detection of the Bose-Einstein condensation of NaRb molecules*

Recent achievements in degenerate dipolar molecular gases [1,2,3,4] point an exciting future of exploration of many body system with tunable, long range, anisotropic interaction. Detection of such low temperature quantum gases and avoiding extra heating are crucial steps to extract the real information. Here we report on a method to detect the BEC of NaRb molecules [4]. Our approach contains two parts. We control the Raman laser beams by a galvo to follow the dropping of microwave shielded ground state molecules during time of flight and dissociate the ground state molecules to free atoms at the end of TOF by STIRAP pulse for detection. We demonstrate that this method can significantly suppress the loss and avoid heating during final detection and help us to distinguish the different phases of condensates.