Key points are not available for this paper at this time.
We report the first observation of second harmonic generation associated with intersubband transitions in AlInAs/GaInAs quantum wells. The measured second order susceptibility in our new asymmetric coupled well structure lattice matched to InP is 4.8×10−8 m/V, about 100 times larger than bulk values in InP, GaAs, and InAs.
Sirtori et al. (Mon,) studied this question.