Terahertz nonlinear optics with strained p-type quantum wells

Valence-subband nonparabolicity is shown theoretically to lead to nonlinearities associated with terahertz third-harmonic generation in strained p -type quantum wells. For strained InAs quantum wells it is found that the corresponding value of chi((3)) can be as large as ~10(-12)(m/V)(2). The predicted values of chi((3)) are in the range of those associated with intersubband transitions in the mid-infrared region of the spectrum.