The p-Ge THz laser in low B-field: properties under pulsed and mode locked operation

A detailed study of the optical output of the p-Ge hot hole laser, emitting in the THz range, has been started for (normal) pulsed- as well as for active mode locked operation. Results on wavelength dependent gain and pulse shape for the low magnetic field action range under long pulsed operation are presented. The recently developed technique to achieve active mode locking is described. Results on the shape of the pulses in the small signal gain as well as in the saturated gain regime under mode locked operation are given; FWHM pulse widths of 100 ps have been observed.