A quantum computer is proposed in which information is stored in the two
lowest electronic states of doped quantum dots (QDs). Many QDs are located in a
microcavity. A pair of gates controls the energy levels in each QD. A
Controlled Not (CNOT) operation involving any pair of QDs can be effected by a
sequence of gate-voltage pulses which tune the QD energy levels into resonance
with frequencies of the cavity or a laser. The duration of a CNOT operation is
estimated to be much shorter than the time for an electron to decohere by
emitting an acoustic phonon.Comment: Revtex 6 pages, 3 postscript figures, minor typos correcte