EXCITONIC EMISSION IN ZNCDSE-ZNSE MULTIPLE-QUANTUM WELLS

Zn1-xCdxSe-ZnSe multiple quantum wells (MQWs) are grown on GaAs (100) substrate by MOCVD. Their photoluminescence (PL) is studied at tempera tures between 77 and 300 K. We have observed five emission bands in Zn 0.68Cd0.32Se-ZnSe MQWs under the 457.9 nm line of an Ar ion laser exci tation at 77 K for the first time. Three of these bands are attributed to different exciton emission: the n = 1 heavy-hole (HH) exciton tran sition, the n = 1 light-hole (LH) exciton transiton and the n = 1 HH e xciton transiton with the emission of two LO phonons. The two exciton emission bands P2 and P3 of n = 1 HH and n = 1 HH with two LO phonons emission can be observed up to 230 K.