Terahertz Wave p-type Ge Laser.

Terahertz wide range tunable cyclotron resonance p-Ge laser

We present a Terahertz (THz) p-Ge laser operating in a cyclotron resonance (CR) mode. Thanks to the use of the optimum crystallographic orientation of p-Ge with respect to crossed E B fields, the laser line frequency is continuously tunable in the range 1.2-2.8 THz (40-90 cm) with the linewidth being 6 GHz (0.2 cm). We also show that due to such a wide CR radiation range, the laser can serve as...

Broad band p-Ge optical amplifier of terahertz radiation

A solid state broad band amplifier of terahertz radiation ~1.5–4 THz!, based on intersubband transitions of hot holes in p-Ge is demonstrated. The gain is investigated as a function of applied magnetic and electric fields by transmission measurements using a laser system with two p-Ge active crystals, when one operates as an oscillator and one as an amplifier. A peak gain higher than usually re...

Enhancement of terahertz wave generation from laser induced plasma

Terahertz quantum-cascade laser with active leaky-wave antenna

We report the demonstration of a one-dimensional waveguide for terahertz quantum-cascade (QC) lasers, which acts as a leaky-wave antenna and tailors laser radiation in one dimension to a directional beam. This scheme adapts microwave transmission-line metamaterial concepts to a planar structure realized in terahertz metal-metal waveguide technology. The active leaky-wave antenna is fed by a mas...

Far-infrared p-Ge laser with variable length cavity

Operation of a far-infrared (1.5–4.2 THz) p-Ge laser in an open quasi-optical resonator is demonstrated. This contrasts with previous designs where mirrors were fixed to surfaces of the active crystal. Enhanced stability and tuning of the laser cavity length are demonstrated, which are steps toward continuous tunability without mode-hops. 2002 Elsevier Science B.V. All rights reserved. PACS: 42...