Novel design concepts of widely tunable germanium terahertz lasers

We explore the full parameter space for laser operation and compile guidelines for building improved Ge lasers, especially for continuous wave applications. We present laser emission from p-type Ge lasers with small volumes at high repetition rates and with inter-contact distances as low as 750 mu m The emission is analyzed as a function of the current-voltage characteristic. The Poisson equation is solved to determine the electric field distribution and two new laser designs are presented. (C) 1999 Elsevier Science B.V. All rights reserved.