Confinement of acoustical vibrations in a semiconductor planar phonon cavity

TRIGO M, BRUCHHAUSEN A, FAINSTEIN A, JUSSERAND B, THIERRY-MIEG V

PHYSICAL REVIEW LETTERS

Año: 2002 vol. 89 p. 227402 - 227402

0031-9007

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.