Coherent control of nuclear-spin system in a quantum-Hall device

Coherent control of local nuclear spins in a solid-state device is demonstrated. By unequally populating spin-resolved quantum-Hall edge channels, nuclear spins in a limited region along the edge channels are strongly polarized via the hyperfine interaction. Pulsed rf magnetic fields, generated by a built-in micrometal strip, cause the nuclear-spin state to evolve coherently. The nuclear-spin state reached during the pulse duration is finally read out via the edge-channel conductance, which shows Rabi oscillation. (C) 2003 American Institute of Physics.