Handheld terahertz systems based on telecom technologies

The potential of Terahertz technology for various applications in security or material inspection has now been demonstrated widely. However, THz systems have to shrink in size and price to become acceptable for real-world applications. Our way to approach this target is to exploit technologies developed and matured originally for 1.55 m fiber-optic telecom applications. Key devices are photoconductive antennas for 1.55 m operation. They were developed using a novel InGaAs/InAlAs multi-layer structure. The antennas are packaged into fiber coupled modules. These handheld THz heads are driven by a 1.55 m pulsed fiber laser. A tunable delay with both an oscillating mirror and a precise linear drive allow for real-time measurements as well as for high resolution spectroscopy. The system performance up to 4 THz is demonstrated.