Fig. 4: Dynamics of the nonlinear response as a function of pump intensity.
From: Ultrafast terahertz saturable absorbers using tailored intersubband polaritons
a Integrated PP signal (red curve) as a function of peak intensity of the incident THz pulses. The blue line indicates the experimental values for a bare ISB transition. The error bars state the systematic uncertainty of the determination of the peak intensity. b Corresponding curves for the 4WM signal.
