Simplifying an ultrafast laser offers better control

May 14, 2014 by Stéphanie Thibault

Going back to the drawing board to find a way to overcome the technical limitations of their laser, a team led by François Légaré, professor at the INRS Énergie Matériaux Télécommunications Research Centre, developed a new concept offering a simpler laser design, control over new parameters, and excellent performance potential. Called "frequency domain optical parametric amplification" (FOPA), the concept supersedes traditional time domain amplification schemes that have been the linchpin of ultrafast laser science for 20 years. The new concept is explained in detail in an open access article in Nature Communications.

For researchers, capturing images of a moving electron is the holy grail of molecular imaging. But in their efforts to generate a that is sufficiently short and powerful to capture such an image, researchers have been held back by the fundamental limitations and unsatisfactory performance of lasers. "Our goal is to capture images of a chemical reaction using high spatial and temporal resolution," explained François Légaré, speaking at the TEDxConcordia event. "I want to shoot a video where you can actually see the atoms dancing in a chemical reaction."

Amplifying laser pulses in the frequency domain rather than the time domain also overcomes certain technical constraints, among them the ability to access multiple different frequencies simultaneously and control them independently. In addition, higher light pulse energy can be achieved with the new concept. "Our approach holds promise for high-power, broad spectrum, few-cycle laser sources," said the young researcher.

In the proof of concept presented in the Nature Communications article, Professor Légaré's team demonstrated that FOPA generates pulses comparable to lasers using time domain amplification in the given conditions: 1.5 mJ, 1.8 microns, 12 fs duration corresponding to 2 optical cycles. Research associate and lead author Bruno Schmidt points out that not only does the FOPA approach open up access to parameters that could not previously be controlled, it also eliminates many complex assembly components. "The logic underpinning this concept could be applied to other types of applications," he added, "so we believe it will allow us to look at nonlinear optics in a whole new light." Optimistic and ambitious, Bruno Schmidt plans to market the innovations stemming from his work, even founding his own company, few-cycle Inc.

Explore further: Nonlinear optical materials convert terahertz radiation into infrared light

More information: The article entitled "Frequency domain optical parametric amplification" appeared in the Nature Communications journal on May 7, 2014.… full/ncomms4643.html

add to favorites email to friend print save as pdf

Related Stories

X-rays in the fast lane

May 10, 2013

X-ray free-electron lasers (XFELs) produce higher-power laser pulses over a broader range of energies compared with most other x-ray sources. Although the pulse durations currently available are enormously ...

High power laser sources at exotic wavelengths

Apr 14, 2014

High power laser sources at exotic wavelengths may be a step closer as researchers in China report a fibre optic parametric oscillator with record breaking efficiency. The research team believe this could ...

Steering chemical reactions with laser pulses

Apr 23, 2014

With ultra-short laser pulses, chemical reactions can be controlled at the Vienna University of Technology. Electrons have little mass and are therefore influenced by the laser, whereas the atomic nuclei ...

Recommended for you

New filter could advance terahertz data transmission

Feb 27, 2015

University of Utah engineers have discovered a new approach for designing filters capable of separating different frequencies in the terahertz spectrum, the next generation of communications bandwidth that ...

The super-resolution revolution

Feb 27, 2015

Cambridge scientists are part of a resolution revolution. Building powerful instruments that shatter the physical limits of optical microscopy, they are beginning to watch molecular processes as they happen, ...

Precision gas sensor could fit on a chip

Feb 27, 2015

Using their expertise in silicon optics, Cornell engineers have miniaturized a light source in the elusive mid-infrared (mid-IR) spectrum, effectively squeezing the capabilities of a large, tabletop laser onto a 1-millimeter ...

A new X-ray microscope for nanoscale imaging

Feb 27, 2015

Delivering the capability to image nanostructures and chemical reactions down to nanometer resolution requires a new class of x-ray microscope that can perform precision microscopy experiments using ultra-bright ...

New research signals big future for quantum radar

Feb 26, 2015

A prototype quantum radar that has the potential to detect objects which are invisible to conventional systems has been developed by an international research team led by a quantum information scientist at the University ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.