Abstract

The idea of controlling physical and chemical properties of matter through the coherence properties of light has long captured the interest of the scientific community [1]. Here we report coherent generation and control of a photocurrent in a bulk, unbiased semiconductor when both initial and final states are in the continuum (valence and conduction bands). One- and two-photon absorption connecting the same states induce a polar distribution of carriers in k-space, and therefore, a photocurrent whose direction and magnitude depend on the relative phase between the beams [2]. Our experiments were performed at 295 K with bulk low-temperature-grown GaAs using phase-related pulses at 1550 and 755 nm (ω and 2ω beams).

© 1996 Optical Society of America