Resonance Raman spectroscopy and excitation profile of CdxZn1-xSe/ZnSe quantum wires

We present resonance Raman spectra obtained from CdZnSe/ZnSe quantum wires and short wires with different wire lengths and widths and cadmium contents of 20%. The spectra show high outgoing resonances for the LO overtones (2L O and 3LO). For two wire sizes ((a): length L = 100 mu m, width W = 18 nm; (b): L = 49 nm, W = 27 nm) excitation profiles of the LO fundamental and of the first overtone of Cd0.2Zn0.8Se quantunl wires have been recorded. The excitation profiles clearly show structures attributed to the incoming and outgoing resonances. Furthermore, both luminescence intensity and the inten sity ratio 2LO/1LO show a decrease with increasing sample age due to aging effects, whereas the phonon wavenumber positions are not affected by the sa mple age. (C) 2000 Elsevier Science B.V. All rights reserved.