Direct observation of hyperpolarization breaking through the spin diffusion barrier Stern, Quentin ; Cousin, Samuel François ; Mentink-Vigier, Frédéric ; Pinon, Arthur César ; Elliott, Stuart James ; Cala, Olivier ; Jannin, Sami Abstract Publication: Science Advances Pub Date: April 2021 DOI: 10.1126/sciadv.abf5735 Bibcode: 2021SciA....7.5735S