Three color coherent generation and control of current in low-temperature-grown GaAs

We demonstrate coherent generation and control of electrical currents in lo w-temperature-grown GaAs at 300 K using three phase-related, 150 fs pulses derived from a parametric process. Interference between single photon (0.8 mu m) and nondegenerate two photon (1.4 and 1.8 mu m) absorption amplitudes generates ballistic electrical currents whose beam polarization dependence is in agreement with a simple Fermi's golden rule calculation. (C) 1999 Am erican Institute of Physics. [S0003-6951(99)01914-2].