RAMAN-SCATTERING FROM CONFINED PHONONS IN GAAS ALGAAS QUANTUM WIRES/

We report on photoluminescence and Raman scattering performed at low t emperature (T = 10 K) on GaAs/Al0.3Ga0.7As quantum-well wires with eff ective wire widths of L = 100.0 and 10.9 nm prepared by molecular beam epitaxial growth followed by holographic patterning, reactive ion etc hing, and anodic thinning. We find evidence for the existence of longi tudinal optical phonon modes confined to the GaAs quantum wire. The ob served frequency at omega(L10) = 285.6 cm(-1) for L = 11.0 nm is in go od agreement with that calculated on the basis of the dispersive diele ctric continuum theory of Enderlein dagger as applied to the GaAs/Al0. 3Ga0.7As system. Our results indicate the high crystalline quality of the quantum-well wires fabricated using these techniques. (C) 1998 Aca demic Press.