  Conduction electrons are used to optically polarize, detect and manipulate
nuclear spin in a (110) GaAs quantum well. Using optical Larmor magnetometry,
we find that nuclear spin can be polarized along or against the applied
magnetic field, depending on field polarity and tilting of the sample with
respect to the optical pump beam. Periodic optical excitation of the
quantum-confined electron spin reveals a complete spectrum of optically-induced
and quadrupolar-split nuclear resonances, as well as evidence for delta m = 2
transitions.
