Time-integrated photoluminescence for all three samples for the same fluence. In this case, the frequency doubled output of a femtosecond Ti:Sapphire laser was tuned to 400 nm. This pump wavelength was sufficiently long to be absorbed only by the quantum well material. As expected, the PL intensity is proportional to the total length of the quantum wells within the intrinsic region. There was no evidence of yellow emission for the carrier densities excited with the given fluence at 400 nm.
© 1999 The Materials Research Society
