Novel optical properties of Zn1-xMnxSe1-yTey epilayers grown by molecular beam epitaxy

Zn1-xMnxSe1-yTey (x less than or equal to 0.78, 0 less than or equal to y less than or equal to 1) epilayers were grown on the GaAs (001) substrate with substrate tilt angle 0 degrees, 3 degrees, 10 degrees, and 15 degrees towards [010] by molecular beam epitaxy. In case of ZnSe1-yTey epilayers, a blue shift of 5 meV was found as the substrate tilt angle increased from 0 degrees to 15 degrees. Whereas in the case of Zn1-xMnxSe epilayers, a red shift of 4 meV was found as the substrate tilt angle increased from 0 degrees to 15 degrees. The blue (red) shift in band gap energy is attributed to the increasing incorporation of smaller Se (Zn) ion with the increase in the kink density which results from the increase in the substrate tilt angle. In addition, a novel photoluminescence channel is proposed to explain the enhanced photoluminescence of the intra-Mn2+ ion transition, (6)A(1) to T-4(1) transitions. (C) 1999 Elsevier Science S.A. All rights reserved.