Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Catching the wave: researchers measure very short laser pulses

04.12.2006
Scientists have perfected a technique for very accurately measuring and controlling the electromagnetic waves within some of the shortest laser pulses ever made, says new research published today. Being able to fully understand and control these laser pulses represents an important step towards using them to track and manipulate electrons in leading-edge research at the sub-atomic level.

The study, published in Nature Physics, focused on extremely short laser pulses, less than 10 femtoseconds long - a femtosecond is one million-billionth of a second. These laser pulses can allow scientists to move and control the electrons in atoms and molecules, and to understand, for example, how molecules are formed. To achieve this reliably, the pulse of electromagnetic waves emitted from the laser must be controlled and measured with a precision which, until now, has been very hard to achieve.

The team of physicists from Imperial College London attained an unprecedented level of accurate measurement by firing the femtosecond laser pulse into a sample of gas, which responds by emitting an x-ray pulse which is even shorter in duration - up to 10 times shorter than the original laser pulse. The researchers found that the spectrum of the x-ray pulse has encoded within it all the information necessary to precisely reconstruct the waveform of the original laser pulse. Through careful measurements and some 'intelligent' software designed specifically for this purpose, the researchers were therefore able, for the first time, to measure the waveform of individual femtosecond pulses.

Dr John Tisch, one of the Imperial research team, said: "This measurement technique is so accurate that we can determine the position of a peak in the pulse of electromagnetic waves from the laser with a precision of a mere 0.05 femtoseconds - in other words, 50 attoseconds. Also, the measurement can be made on individual pulses rather than by looking at the average properties of many pulses, so this is an important step forwards."

Dr Tisch explains that not only will this new technique lead to a greater ability to use short laser pulses for accurate sub-atomic level research, but it also sheds new light on the extremely short x-ray pulses emitted in response: "The x-ray pulses we used in the measurement process of our research are of great interest in their own right," he says. "They are on the attosecond timescale, which is even shorter than a femtosecond - just one billion-billionth of a second. They are a new tool for scientists to probe even faster motion than the femtosecond pulses that triggered them."

The research team have recently received a four-year £2.5 million grant from the EPSRC to take this research to the next stage. Professor Jonathan Marangos explains: "Now we've perfected this technique, we are going to look into using our accurate measurements and control of these lasers to manipulate electrons and control quantum processes."

The research was funded by a Basic Technology Programme grant from RCUK.

Laura Gallagher | alfa
Further information:
http://www.imperial.ac.uk

More articles from Physics and Astronomy:

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

nachricht NASA's fermi finds possible dark matter ties in andromeda galaxy
22.02.2017 | NASA/Goddard Space Flight Center

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

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>