Resonance Raman scattering of single and stacked mono- and submono-layers of CdSe in ZnSe

• Published in: Solid state communications Vol. 112; no. 6; pp. 351 - 355
• Main Authors: Reshina, I.I., Toropov, A.A., Ivanov, S.V., Mirlin, D.N., Keim, M., Waag, A., Landwehr, G.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.1999
• Subjects: A. Nanostructures; A. Semiconductors; D. Phonons; E. Inelastic light scattering; D. Phonons; A. Nanostructures; E. Inelastic light scattering; A. Semiconductors
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/S0038-1098(99)00348-8

Resonance Raman scattering of phonons in CdSe/ZnSe superlattices with mono- and submono-layer depositions of CdSe was studied at different temperatures. On the basis of transmission electron microscopy and optical studies it is now widely believed that such depositions lead to formation of flat CdZnSe islands with 10–100 nm lateral dimensions. Strong resonance Raman scattering by LO-phonon of ZnSe was observed at room temperature. At temperature about 20 K resonance Raman spectra showed a broad structured phonon peak that could be deconvoluted into a narrow peak attributed to ZnSe and a broad peak at lower frequency, which gained intensity as the excitation energy was tuned closer to the exciton transition. We attribute this peak to averaged scattering of LO-phonons in the CdZnSe islands with different Cd composition. These results confirm exciton localization in the islands at low temperatures. Folded acoustic phonons of the superlattices were observed.