Photocarrier-induced reduction of the lifetime of acoustic phonons in semiconductor superlattices

MARÍA FLORENCIA PASCUAL-WINTER, ALEJANDRO FAINSTEIN, BERNARD JUSSERAND, BERNARD PERRIN, AND ARISTIDE LEMAÎTRE

CHINESE JOURNAL OF PHYSICS

PHYSICAL SOC REPUBLIC CHINA

Lugar: Taipei; Año: 2011 vol. 49 p. 250 - 258

0577-9073

We present an experimental analysis of the role of the electron-phonon interaction in the lifetime of coherent longitudinal acoustic phonons in a sample based on the GaAs/AlAs superlattice structure. Sub-terahertz phonons are generated and detected through an ultra-fast pump-probe technique. In order to supply with different scenarios for the electron-phonon interaction, two experimental configurations are proposed, either with a high or a nil density of photo-excited carriers in the spatial region where the phonon detection takes place. We observe a one-order-of-magnitude reduction in the phonon lifetime in the first case with respect to the second.