Resistively detected nuclear magnetic resonance in the quantum Hall regime: Possible evidence for a Skyrme crystal

Resistively detected nuclear magnetic resonance measurements have been performed on a high mobility heterostructure in the quantum Hall regime. At millikelvin temperatures the nuclear resonances are observed in the vicinity of various integer and fractional filling factors without previous dynamic nuclear polarization. Near nu = 1, the observed large enhancement of the resonance amplitude accompanied by a reduction of T-1 strongly suggests a greatly increased coupling between the electronic and nuclear spin systems. This is consistent with the proposed coupling of the nuclear spin system to the Goldstone mode of the Skyrme crystal.