Coherent Control of Light Absorption and Carrier Dynamics in Semiconductor Nanostructures

We present two examples of coherent control of inter(sub)band transitions in a semiconductor double well by coherent light sources. Accounting for the upper hole subband and two lowest electron subbands, a microscopic theoretical analysis shows that electron-hole pair generation by a sub-picosecond pump pulse can be controlled by the intensity and the phase of a dc microwave field which resonantly couples the two electron subbands. Light absorption can be either enhanced or reduced. Secondly, it is shown that proper combination of two pulsed laser fields allows control of electron inter(sub)band transitions and final-state population, i.e., the formation of indirect versus direct excitons.