Optical properties of CdTe/ZnTe self-assembled quantum dots: Raman and photoluminescence spectroscopy

The properties of 3 monolayers (ml) CdTe self-assembled quantum dot (SAQD) sample are investigated by means of Raman and photoluminescence (PL) spectroscopy. The PL spectrum is characterized by two main emission peaks, both connected with the existence of QDs. One presents direct deexcitation to ground state and the other one is optical phonon ( ω = 204.2 cm −1 ) assisted deexcitation. One-phonon Raman spectra at room temperature show surface-optical phonon at 201 cm −1 . At temperatures below 200 K, multiphonon processes are registered. Multiphonon maximum depends on the temperature, and laser energy.