Non-equilibrium fractional quantum Hall states visualized by optically   detected MRI
  Using photoluminescence microscopy enhanced by MRI, we visualize in real space both electron and nuclear polarization occurring in non-equilibrium FQH liquids. We observe stripe-like regions comprising FQH excited states which discretely form when the FQH liquid is excited by a source-drain current. These regions are topologically protected and deformable, and give rise to bidirectionally polarized nuclear spins as spin-resolved electrons flow across their boundaries. 
John N. Moore, Junichiro Hayakawa, Takaaki Mano, Takeshi Noda and Go   Yusa
cond-mat.mes-hall