Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Precise molecular fingerprinting on the fly

22.12.2015

Frequency-agile laser frequency combs take real-time multicolour snapshots of absorbing samples.

Electro-optic modulators, which can switch light on and off within just picoseconds, are enabling ever faster telecommunication over optical glass fibres, so that large movies can be streamed more smoothly across oceans into our homes.


Time-domain interference signal of the beats between the two frequency-agile laser combs and part of the resulting spectrum of the CO2 molecule.

Graphic: MPQ, Laser Spectroscopy Division

The same tools have now been harnessed for high-speed and accurate molecular sensing, as reported by an international collaboration around Dr. Nathalie Picqué, Max Planck Institute of Quantum Optics and Ludwig-Maximilians-Universität Munich, in a letter published in Nature Photonics, 21 December 2015. The collaboration partners are with the Laboratoire Interdisciplinaire Carnot de Bourgogne (France) and the Institut des Sciences Moléculaires d’Orsay (France).

Molecules absorb light at well-defined particular colours or optical frequencies. Usually such characteristic frequencies are located in the infrared region of the electromagnetic spectrum. Precisely measuring a set of such absorption dips unambiguously identifies the molecules and quantifies their abundance in the probed environment.

Because detection of molecules by optical absorption spectroscopy is sensitive and nonintrusive, it finds an increasing number of applications, from biomedical diagnostics to atmospheric sensing. In the gas phase, the absorption lines are narrow so that high spectral resolution is needed to distinguish the different lines. Although many powerful spectroscopic techniques have been developed, rapid and precise high-resolution sensing is still a challenge.

A team of scientists at MPQ reports a promising new technique of near-infrared spectroscopy. They use modulators and a nonlinear optical fibre to produce two frequency combs, each with more than a thousand evenly spaced infrared spectral lines with a remarkably flat intensity distribution.

Line spacing and spectral position can be selected quickly and freely by simply dialing a knob. Such frequency-agile optical combs offer unprecedented freedom when interrogating a molecular spectrum via a powerful technique called multiplexed dual-comb spectroscopy.

Two mutually coherent combs are combined in an interferometer. Unprecedented refresh rates (80 kHz) and tuning speeds (10 nm s to the minus 1) at high signal-to-noise ratio are achieved. Such unique combination holds much promise for trace gas sensing, a domain relevant to physics, biology, chemistry, industry or atmospheric sciences.

“Furthermore, the frequency-agile frequency comb generator might also become an enabling tool for applications beyond spectroscopy, like for arbitrary waveform generation, radio-frequency photonics, optical coherence tomography or microscopy”, concludes Dr. Ming Yan, a post-doc working at the experiment.

Original publication:

G. Millot, S. Pitois, M. Yan, T. Hovhannisyan, A. Bendahmane, T.W. Hänsch, N. Picqué
Frequency-agile dual-comb spectroscopy
Nature Photonics, Advance online publication, http://dx.doi.org/10.1038/nphoton.2015.250 (December 21st, 2015)

contact:

Dr. Nathalie Picqué
Max-Planck-Institut für Quantenoptik
Hans-Kopfermann-Str. 1
85748 Garching b. München
Telefon: +49 (0)89 / 32 905 -290
E-Mail: nathalie.picque@mpq.mpg.de

Dr. Olivia Meyer-Streng
Presse- und Öffentlichkeitsarbeit
Max-Planck-Institut für Quantenoptik, Garching b. München
Telefon: +49 (0)89 / 32 905 -213
E-Mail: olivia.meyer-streng@mpq.mpg.de

Dr. Olivia Meyer-Streng | Max-Planck-Institut für Quantenoptik
Further information:
http://www.mpq.mpg.de/

More articles from Physics and Astronomy:

nachricht Tune your radio: galaxies sing while forming stars
21.02.2017 | Max-Planck-Institut für Radioastronomie

nachricht Breakthrough with a chain of gold atoms
17.02.2017 | Universität Konstanz

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>