Scientists at the University of Leeds, the French National Centre for Scientific Research (CNRS) and Denis Diderot University in Paris have created T-ray (terahertz ray) ‘pulses’ from a quantum cascade laser.
This is a major breakthrough where emission of separate packets or pulses of terahertz radiation has been produced from ultra-powered T-rays, which usually generate one constant T-ray beam. The latest development paves new routes for T-rays to develop novel spectroscopy and imaging techniques for analysis of synthetic and natural materials.
T-Ray Pulses
T-ray is a radiation band in the electromagnetic range that lies between visible light and radio waves. T-rays can be employed to determine contaminations in biological and chemical materials, creating typical ‘spectral fingerprints’ that are utilized to determine various materials.
Lately, scientists are showing interests in a technique called terahertz time-domain spectroscopy that uses pulses of T-rays for analyzing materials. So far, laser sources, which produce meager power of about one millionth of a watt, are used to generate these pulses.
Giles Davies and Edmund Linfield of the Electronic and Electrical Engineering of the University of Leeds, and Stefano Barbieri and staffs from Paris have utilized the power of a quantum cascade laser to produce a T-ray pulse train. They also developed a new technique to detect the complete pulse train and confirmed that the technique could be employed for analyzing materials.
The European Research Council programmes 'TOSCA' and ‘NOTES’, The UK Engineering and Physical Sciences Research Council (EPSRC), the National Agency for Research (ANR) (contract HI-TEQ) and the Délégation Générale pour l'Armement supported the research work.