hide
Free keywords:
TEMPERATURE-GROWN-GAAS; THZ SPECTROSCOPYPhysics;
Abstract:
The authors report on photomixing terahertz sources that overcome the transit time versus RC-time trade-off and allow for independent optimization of both of them, using a n-i-p-n-i-p superlattice. Furthermore, they take advantage of ballistic transport for reduced transit times. Apart from more favorable material parameters, In(Al)GaAs photomixers benefit from the advanced telecommunication laser technology around 1.55 mu m as compared to GaAs. In such devices, a terahertz-power output of 1 mu W has been achieved at 0.4 THz at a photocurrent of 3.8 mA. A comparison between corresponding GaAs- and InGaAs-based n-i-p-n-i-p photomixers reveals an improvement of performance by at least an order of magnitude for the latter one. (c) 2007 American Institute of Physics.
