Confinement of acoustical vibrations in a semiconductor planar phonon cavity

M. TRIGO; A. BRUCHHAUSEN; A. FAINSTEIN; B. JUSSERAND; V. THIERRY-MIEG

PHYSICAL REVIEW LETTERS

APS

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 halfwavelength 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.