Confinement of acoustical vibrations in a semiconductor planar phonon cavity.
Extending the idea of optical microcavities to sound waves, we propose a phonon cavity consisting of two semiconductor superlattices enclosing a spacer layer. We show that acoustical phonons can be confined in such layered structures when the spacer thickness is an integer multiple of the acoustic half-wavelength at the center of one of the superlattice folded minigaps. We report Raman scattering experiments that, taking profit of an optical microcavity geometry, demonstrate unambiguously the observation of a phonon-cavity confined acoustical vibration in a GaAs/AlAs based structure. The experimental results compare precisely with photoelastic model calculations of the Raman spectra.
Trigo
M
M
Centro Atómico Bariloche & Instituto Balseiro, C.N.E.A., 8400 San Carlos de Bariloche, Argentina.
Bruchhausen
A
A
Fainstein
A
A
Jusserand
B
B
Thierry-Mieg
V
V