Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Frequency combs for sniffing molecules

11.01.2013
Tiny crystalline resonators produce mid-infrared frequency combs for fingerprinting of molecules.

Most molecules, including those of importance in medical diagnostics or pollution monitoring, have characteristic “fingerprints” in the mid-infrared spectral region. However, state-of-the-art mid-infrared frequency comb techniques require systems that are often costly and limited in their applications.

In an article just published in Nature Communications (January 8th, 2013), scientists of the Laser Spectroscopy Division of the Max-Plank-Institute of Quantum Optics, in a collaboration with the Ecole Polytechnique de Lausanne (Switzerland), the Ludwig-Maximilians-Universität Munich, the Menlo Systems GmbH and the Institut des Sciences Moléculaires d’Orsay (France), have demonstrated the generation of mid-infrared frequency combs with small crystalline micro-resonators. Such miniaturized instruments, which can detect and characterize such molecules quickly and with high sensitivity, could revolutionize many areas of science and technology.

Optical frequency comb generators are coherent light sources, which produce a “comb” of many precisely evenly spaced spectral lines. During the last decade, such combs have revolutionized the art of measuring the frequency of light, as recognized in 2005 by the award of the Physics Nobel Prize to Prof. Theodor W. Hänsch. Today frequency combs are becoming enabling tools for new and unexpected applications. In particular, frequency combs are strongly impacting molecular spectroscopy by dramatically improving the recording speed, the resolution and the accuracy of Fourier spectrometers. The mid-infrared spectral range, also called molecular fingerprint region, is of primary importance to molecular physics. However, as reviewed in an article* published in the July 2012 issue of Nature Photonics, emerging mid-infrared frequency comb techniques still need considerable improvements: the systems are often based on nonlinear frequency conversion of near-infrared laser sources, which makes them bulky, and their use is limited to specialists.

The new technique developed by a team of scientists at MPQ avoids these obstacles. Here, mid-infrared frequency comb radiation is generated by exciting whispering gallery modes in a small toroidal monolithic resonator. A crystalline micro-resonator with a quality-factor exceeding 109 is pumped by a continuous-wave laser. By a nonlinear process called four-wave mixing, it produces a broad comb spectrum consisting of discrete lines spaced by 100 GHz at mid-infrared wavelengths near 2.5 µm. “The remarkable characteristics of such comb generators are their small size, large line-spacing, high power per comb line, and efficient conversion,” says Dr. Christine Wang, the post-doc who has performed the experiment. “An appropriate choice of the material – here magnesium fluoride – and proper engineering are crucial to realize broad spectral span and low-phase noise, as required for frequency comb operation.” Such miniaturized sources hold much promise for on-chip frequency-comb spectrometers. The spectrum of the fundamental vibrations of liquid phase samples might be measured within a few nanoseconds with a similar refresh time!

*A. Schliesser, N. Picqué, T.W. Hänsch, Mid-infrared frequency combs, Nature Photonics 6, 440-449 (2012)

Original publication:
C.Y. Wang, T. Herr, P. Del’Haye, A. Schliesser, J. Hofer, R. Holzwarth, T.W. Hänsch, N. Picqué and T.J. Kippenberg
Mid-infrared optical frequency combs at 2.5 μm based on crystalline microresonators
Nature Communications 4, Article number: 1345, Issue of January 8th, 2013.
DOI: 10.1038/ncomms2335
Contact:
Prof. Dr. Theodor W. Hänsch
Max-Planck-Institute of Quantum Optics
Hans Kopfermann-Strasse 1
85748 Garching
Phone: +49 (0) 89 32905 -712
E-mail: t.w.haensch@mpq.mpg.de
Dr. Olivia Meyer-Streng
Press & Public Relations
Max-Planck-Institute of Quantum Optics
Phone: +49 (0) 89 32 905 -213
Fax: +49 (0) 89 32 905 -200
E-mail: olivia.meyer-streng@mpq.mpg.de
Dr. Nathalie Picqué
Max-Planck-Institute of Quantum Optics & Centre National de la Recherche
Scientifique
Phone: +49 (0) 89 32905 -290
E-mail: nathalie.picque@mpq.mpg.de
Prof. Tobias J. Kippenberg
Ecole Polytechnique Fédérale de Lausanne
Laboratory of Photonics and Quantum Measurements
Lausanne, Switzerland
Email: tobias.kippenberg@epfl.ch

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

More articles from Physics and Astronomy:

nachricht Smallest transistor worldwide switches current with a single atom in solid electrolyte
17.08.2018 | Karlsruher Institut für Technologie (KIT)

nachricht Protecting the power grid: Advanced plasma switch for more efficient transmission
17.08.2018 | DOE/Princeton Plasma Physics Laboratory

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: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>