Theory of NMR in semiconductor quantum point contact devices

We describe how a local nonequilibrium nuclear polarization can be generated and detected by electrical means in a semiconductor quantum point contact device. We show that measurements of the nuclear-spin-relaxation rate will provide clear signatures of the interaction mechanism underlying the 0.7 conductance anomaly. Our analysis illustrates how nuclear-magnetic-resonance methods, which are used extensively to study strongly correlated electron phases in bulk materials, can be made to play a similarly important role in nanoscale devices.