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<p>Recordamos el coloquio de hoy,<br>
<br>
<br>
<br>
COLOQUIOS DEL DEPARTAMENTO DE FÍSICA FCEYN - UBA<br>
<br>
En el Aula Seminario, 2do piso, Pab. I, <br>
<br>
Jueves 7/3, 14hs:<br>
<br>
Bernard Jusserand<br>
<br>
Institut Des Nanosciences De Paris, UPMC-CNRS.<br>
<br>
<br>
<br>
<br>
SON ET LUMIèRE : A COMBINED ENGINEERING OF PHOTONS AND ACOUSTIC PHONONS IN<br>
SEMICONDUCTOR NANOSTRUCTURES<br>
<br>
Abstract:<br>
Semiconductor superlattices are periodic stacks of two different<br>
materials, such as GaAs and AlAs, well known for their novel electronic and<br>
photonic properties. In this talk, I will present the ideas which we<br>
developed in the past years, how to transfer the same ideas to the field of<br>
acoustic phonons in multilayers. I will recall the concepts of folded<br>
acoustic phonon in a periodic multilayer stack and of cavity phonons in a<br>
novel device: the acoustic nanocavity.<br>
<br>
Using pump-probe and Raman scattering experiments, we have demonstrated<br>
that the acoustic nanodevices are very efficient generators and detectors<br>
of quasi-monochromatic acoustic wave packets up to frequencies around 1 THz<br>
and that their properties can be widely engineered by adjusting the devices<br>
parameters and the transduction wavelength. High resolution Raman<br>
scattering (10-2 cm-1) also allowed us to determine the lifetime of<br>
acoustic phonons confined in nanocavities.<br>
<br>
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