Spectroscopy method IDs, quantifies molecular species in real time

Feb. 28, 2014
An international team of scientists has developed a real-time identification and quantification method for molecules.

A team of scientists at the Laser Spectroscopy Division of the Max Planck Institute of Quantum Optics (MPQ; Garching, Germany), Ludwig Maximilian University (LMU; Munich, Germany), and the Institut des Sciences Moléculaires d’Orsay (France) has developed a real-time identification and quantification method for molecules. The work has implications in areas such as bioimaging, where real-time recording of molecular spectra is important.

Related: Wavelength-modulated Raman spectroscopy enables tissue assessment in real time

Dual-comb spectroscopy has demonstrated exciting potential for ultra-rapid recording of complex molecular spectra. When compared to state-of-the-art instrumentation used in Fourier transform spectroscopy, it shortens recording times from seconds to microseconds. Dual-comb spectroscopy without moving parts harnesses two laser frequency combs (coherent sources that emit a regular train of ultrashort pulses) to perform interferometric measurements, but it is difficult to synchronize the two lasers within the required precision. Recognizing this, the research team developed a new approach that enabled them to use unstabilized free-running femtosecond lasers without sacrificing performance. By generating proper clock signals, they compensated for laser short-term instabilities by electronic signal processing only.

Related: Ultrafast pulses for precision procedures

Portion of a dual-comb real-time absorption spectrum of acetylene in the near-infrared (NIR) region. While the spectrum without the adaptive sampling (blind sampling) is strongly distorted, the adaptive spectrum accurately reveals the molecular profiles. (Image courtesy of MPQ/Laser Spectroscopy Division)

The possibility of using femtosecond lasers without any sophisticated stabilization scheme considerably eases the implementation of a dual-comb spectrometer. "It should facilitate applications to real-time sensing," comments Takuro Ideguchi, who just completed his doctoral dissertation partly based on this experiment. "Dual-comb spectroscopy holds much promise for new approaches to molecular physics and our scheme of adaptive sampling is a key to their efficient implementation. Enhanced sensitivity for weak concentrations is within reach with the development of mid-infrared frequency combs, while nonlinear dual-comb spectroscopy provides intriguing prospects for applications ranging from bioimaging to precision spectroscopy."

Full details of the work appear in the journal Nature Communications; for more information, please visit http://dx.doi.org/10.1038/ncomms4375.

-----

Follow us on Twitter, 'like' us on Facebook, and join our group on LinkedIn

Subscribe now to BioOptics World magazine; it's free!

Sponsored Recommendations

March 31, 2025
Enhance your remote sensing capabilities with Chroma's precision-engineered optical filters, designed for applications such as environmental monitoring, geospatial mapping, and...
March 31, 2025
Designed for compatibility with a wide range of systems, Chroma's UV filters are engineered to feature high transmission, superior out-of-band blocking, steep edge transitions...
March 31, 2025
Discover strategies to balance component performance and system design, reducing development time and costs while maximizing efficiency.
March 31, 2025
Explore the essential role of optical filters in enhancing Raman spectroscopy measurements including the various filter types and their applications in improving signal-to-noise...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!