One such system is a Bose-Einstein condensate with spin-orbit coupling, which has a supersolid stripe phase 5-8 . Despite several recent studies of this system 9-11 , which studied the miscibility of the spin components 5 , the presence of stripes has not been detected. Here we report the direct observation of the predicted density modulation of the stripe phase using Bragg reflection. Our work establishes a system with * These authors contributed equally to this work. § junruli@mit.edu † Although the original observation of supersolidity 3 turned out to be caused by unusual elastic properties, experiments revealed quantum plasticity and mass supertransport, probably created by superfluid flow through the cores of interconnected dislocations 1,4

The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. CitationRvachov Terms of UseArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. We create fermionic dipolar 23 Na 6 Li molecules in their triplet ground state from an ultracold mixture of 23 Na and 6 Li. Using magnetoassociation across a narrow Feshbach resonance followed by a two-photon stimulated Raman adiabatic passage to the triplet ground state, we produce 3 × 10 4 ground state molecules in a spin-polarized state. We observe a lifetime of 4.6 s in an isolated molecular sample, approaching the p-wave universal rate limit. Electron spin resonance spectroscopy of the triplet state was used to determine the hyperfine structure of this previously unobserved molecular state. Long-Lived Ultracold Molecules with Electric and Magnetic Dipole Moments

Collisional cooling is crucial to prepare quantum degenerate gases. It has been a long-standing goal to achieve such cooling of ultracold molecules. We realize collisional cooling by sympathetically cooling rovibrational ground-state triplet NaLi molecules with Na atoms. We find a lower bound on the elastic to inelastic collision ratio greater than 50. Using two stages of evaporation, the phase-space density of the molecules is increased by a factor of 20, achieving temperatures as low as 220 nK.