Coherent control of acoustic phonons in semiconductor superlattices

Summary form only given.We report on experiments demonstrating the complete quenching of the first-order coherent amplitude by carefully adjusting the laser intensities with respect to the resonant excitation mechanism. The experiments are performed with 50-fs laser pulses derived from a Kerr-lens modelocked Ti:sapphire laser resonantly tuned to the first electron heavy-hole interband resonance of the superlattices. The coherently excited phonon modes are detected in time resolved reflectivity and transmission changes recorded with a fast-scanning delay generator.