We present a theory of the optical control of the spin of an electron in an
InAs quantum dot. We show how two Raman-detuned laser pulses can be used to
obtain arbitrary single-qubit rotations via the excitation of an intermediate
trion state. Our theory takes into account a finite in-plane hole g-factor
and hole-mixing. We show that such rotations can be performed to high
fidelities with pulses lasting a few tens of picoseconds.Comment: 6 pages, 4 figures; minor changes, J-ref adde