News Article
Toptica’s Terabeam THz Spectrometer is Speedy & Small
The cw (continuous wave) system incorporates 1.5 micron lasers using InGaAs/InP emitter and detector technology developed by the Fraunhofer Institute.
At the forthcoming Photonics West exhibition, Toptica Photonics will present its most compact frequency-domain terahertz (THz) spectrometer built to-date.
The system combines Toptica’s new TeraBeam, a highly integrated two-color diode laser, with newly developed InGaAs/InP emitter and detector technology. This has been developed by the Fraunhofer Heinrich-Hertz Institute (HHI), Berlin, Germany.
The new cw THz system features a fast scan option, which reduces the acquisition times in cw THz spectroscopy by more than two orders of magnitude and acquires a complete THz spectrum (e.g. 50-1200 GHz, sub-GHz resolution) in less than a minute.
Until now, research in the field of frequency-domain (cw) terahertz has largely been carried out with GaAs photomixers, requiring laser wavelengths below 870 nm. Whilst excellent results in terms of bandwidth and signal quality have been obtained, the complexity of the optical source and a variety of non-standard optical components resulted in a price level inadequate for widespread industrial use.
HHI & Toptica’s alternative solution uses lasers and antenna packages for cw THz at a telecom wavelength of 1.5 μm. The new TeraBeam represents a compact two-color laser, with a footprint of only 161 x 130 x 61 mm³.
Making use of highly integrated distributed Bragg reflector (DFB)laser diodes and fiber components, the laser provides 30 mW per two-color output and is thus ideally suited to the power requirements of the cw THz emitters and detectors. The emitter utilizes a high-bandwidth photodiode with an integrated waveguide structure, and provides output levels in the microwatt range. The receiver employs an InGaAs photoconductor and achieves excellent SNR values up to 80 dB. The modules are fully packaged with SM/PM fiber pigtails.
The new cw THz system achieves, according to Toptica, for the first time, a measurement speed comparable to that of pulsed spectrometers (e.g. 50-1200 GHz spectrum with sub-GHz resolution in 50 sec). The frequency resolution can be selected via an intuitive graphic user interface and frequency steps as small as 10 MHz are feasible.
The new cw THz system along with the fast scan option will be shown live at Photonics West 2011 in San Francisco at the Toptica booth #817.
