  Achieving coherent population transfer in the solid-state is challenging
compared to atomic systems due to closely spaced electronic states and fast
decoherence. Here, within an atomistic pseudopotential theory, we offer recipes
for the stimulated Raman adiabatic passage in embedded silicon and germanium
nanocrystals. The transfer efficiency spectra displays characteristic Fano
resonances. By exploiting the Stark effect, we predict that transfer can be
switched off with a dc voltage. As the population transfer is highly sensitive
to structural variations, with a choice of a sufficiently small two-photon
detuning bandwidth, it can be harnessed for addressing individual nanocrystals
within an ensemble.
