Next generation 1.5 microm terahertz antennas: mesa-structuring of InGaAs/InAlAs photoconductive layers.

Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, Einsteinufer 37, 10587 Berlin, Germany.
Optics Express (Impact Factor: 3.55). 02/2010; 18(3):2296-301.
Source: PubMed

ABSTRACT Mesa-structuring of InGaAs/InAlAs photoconductive layers is performed employing a chemical assisted ion beam etching (CAIBE) process. Terahertz photoconductive antennas for 1.5 microm operation are fabricated and evaluated in a time domain spectrometer. Order-of-magnitude improvements versus planar antennas are demonstrated in terms of emitter power, dark current and receiver sensitivity.

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