OPNMR — a local probe of spin physics

In the quest to understand (and to make use of) spin effects in mesoscopic systems, the development of new experimental techniques will play a key role. In this review, we will describe some recent work using Optically Pumped Nuclear Magnetic Resonance (OPNMR), a novel spectroscopy that has proven to be an useful probe of electron spin physics in the quantum Hall regimes. We will show: (1) the OPNMR signal from a single GaAs quantum well, (2) the ‘motionally narrowed’ lineshape reflects the variation of the electron density across the ∼300 Å well, and (3) the dramatic changes in the lineshape which provide evidence for Skyrmion localization along the plane of the well.