21 February 2019
Coherent and powerful mid-infrared radiation
Published online 26 September 2015
A team of researchers generate a beam of short, high-power pulses in the mid-infrared region with a repetition rate of one hundred million pulses per second.
Detection of radiation in the mid-infrared region (MIR) is invaluable to scientific discovery, and it has wide-ranging applications in various fields from basic chemistry and life science to forensics and medical diagnostics.
Many molecular signatures lie in the MIR region, a vast number of molecules can therefore be detected and identified by the spectral patterns that result from their interaction with light in that wavelength range.
Owing to the lack of an appropriate lasing material for the MIR region, sources for coherent, powerful MIR radiation have been limited to producing slightly shorter wavelength near-infrared (NIR) laser pulses and passing them through a material that would down-convert the radiation to longer wavelength MIR radiation. However, there has always been a tradeoff between the power that the pulses can carry and the repetition rate of the pulses.
Now, a group of researchers has come up with a setup to generate, for the first time, MIR pulses that combine coherence, high power, and a high repetition rate.
Their discovery promises to markedly boost the dynamic range and sensitivity of instruments that operate on these principles.
Pupeza, I. et al. High-power sub-two-cycle mid-infrared pulses at 100 MHz repetition rate. Nat. Photon. http://dx.doi.org/10.1038/nphoton.2015.179 (2015).