REFLECTANCE OF GAAS (ALGA)AS DISORDERED SUPERLATTICES/

Reflectance spectra of GaAs/Al0.3Ga0.7As disordered superlattices (d-S L) are investigated. The experimental results are compared with numeri cal simulations obtained by means of transfer matrix method. The agree ment between the measured spectra and the numerical calculations indic ate the validity of the model we used, confirming the existence of a d isordered-induced fine structure and the formation of sub-minibands of localized states in d-SL. The temperature dependence of the reflectan ce spectra evidenced an anomalous splitting of some features near the band edge, caused by space charge separation.