Interface vibrational modes and interface structure of CdSe/ZnTe superlattices
نویسندگان
چکیده
Interfacial vibrational modes ~IFM’s! of CdSe/ZnTe superlattice are shown for perfect and atomically rearranged interfaces with four probable exchange configurations. In addition to the IFM at 222 cm originating from single interface Zn-Se ‘‘wrong’’ bonds ~WB’s!, another IFM at 235 cm occurs due to atomic rearrangement at the interfaces, which is attributed to double Zn-Se WB’s. Raman scattering on both atomiclayer-epitaxy and molecular-beam-epitaxy grown samples is reported. Using the experimental data for the 218 cm line of LIF as a base for improving calculations, the corresponding LIF2 line is predicted at 228 cm. Experiments failed to detect this line owing to insufficient double WB’s with long-range order. This characteristic IFM is observed in an annealed sample, with abnormally strong intensity at 227 cm. @S0163-1829~98!01903-1#
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