Nav: Home

Looking at complex light wave forms

May 31, 2017

For the first time an international research team under the direction of Prof. Dr. Giuseppe Sansone at the Institute of Physics at the University of Freiburg has been able to completely characterize the complex evolution of weak electric fields. The team just published its research findings in the scientific journal Nature Photonics.

Light pulses are electromagnetic waves. Their characteristics such as the direction of oscillation, duration and intensity depend on the spatiotemporal evolution of their electric and magnetic fields. Both of these vectors can run in complex trajectories as a light pulse propagates - for instance, they can move along a circle, an elliptical or describe any variation thereof. The movement occurs on a timescale of several hundred attoseconds, which is much faster than any ordinary electronic or optoelectronic device can measure: an attosecond is a billionth of a billionth of a second.

In order to observe how the electric field moves anyway, the team developed a method using a so-called attosecond laser. "Using this new tool we were able to produce electrons in the form of wave packets that only last a few hundred attoseconds," explains Sansone. During their dynamics, electrons are very sensitive to any kind of external disturbance. The researchers leveraged this characteristic to modify the electrons' trajectories with weak visible light pulses. They were then able to measure how the trajectories had been altered, thereby deducing the intensity and direction of the electric field. "Our method will enable researchers in the future to have a complete characterization of electronic dynamics in solids by measuring the visible light reflected on its surface," says Sansone.

Researchers at the University of Jena, Max Planck Institute for Nuclear Physics in Heidelberg, the National Metrology Institute of Germany (PTB) in Braunschweig and the Politecnico in Milan and the Istituto di Fotonica e Nanotecnologie (Institute for Photonics and Nanotechnology) in Padua, Italy, contributed significantly to these findings.
-end-
Original publication:

P. A. Carpeggiani et al. (2017): Vectorial optical field reconstruction by attosecond spatial interferometry.

In: Nature Photonics. DOI 10.1038/nphoton.2017.73

University of Freiburg

Related Evolution Articles:

Artificial evolution of an industry
A research team has taken a deep dive into the newly emerging domain of 'forward-looking' business strategies that show firms have far more ability to actively influence the future of their markets than once thought.
Paleontology: Experiments in evolution
A new find from Patagonia sheds light on the evolution of large predatory dinosaurs.
A window into evolution
The C4 cycle supercharges photosynthesis and evolved independently more than 62 times.
Is evolution predictable?
An international team of scientists working with Heliconius butterflies at the Smithsonian Tropical Research Institute (STRI) in Panama was faced with a mystery: how do pairs of unrelated butterflies from Peru to Costa Rica evolve nearly the same wing-color patterns over and over again?
Predicting evolution
A new method of 're-barcoding' DNA allows scientists to track rapid evolution in yeast.
Insect evolution: Insect evolution
Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich have shown that the incidence of midge and fly larvae in amber is far higher than previously thought.
Evolution of aesthetic dentistry
One of the main goals of dental treatment is to mimic teeth and design smiles in the most natural and aesthetic manner, based on the individual and specific needs of the patient.
An evolution in the understanding of evolution
In an open-source research paper, a UVA Engineering professor and her former Ph.D. student share a new, more accurate method for modeling evolutionary change.
Chemical evolution -- One-pot wonder
Before life, there was RNA: Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich show how the four different letters of this genetic alphabet could be created from simple precursor molecules on early Earth -- under the same environmental conditions.
Catching evolution in the act
Researchers have produced some of the first evidence that shows that artificial selection and natural selection act on the same genes, a hypothesis predicted by Charles Darwin in 1859.
More Evolution News and Evolution Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Climate Mindset
In the past few months, human beings have come together to fight a global threat. This hour, TED speakers explore how our response can be the catalyst to fight another global crisis: climate change. Guests include political strategist Tom Rivett-Carnac, diplomat Christiana Figueres, climate justice activist Xiye Bastida, and writer, illustrator, and artist Oliver Jeffers.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Speedy Beet
There are few musical moments more well-worn than the first four notes of Beethoven's Fifth Symphony. But in this short, we find out that Beethoven might have made a last-ditch effort to keep his music from ever feeling familiar, to keep pushing his listeners to a kind of psychological limit. Big thanks to our Brooklyn Philharmonic musicians: Deborah Buck and Suzy Perelman on violin, Arash Amini on cello, and Ah Ling Neu on viola. And check out The First Four Notes, Matthew Guerrieri's book on Beethoven's Fifth. Support Radiolab today at Radiolab.org/donate.