Featured Research

from universities, journals, and other organizations

Light bursts out of a flying mirror

Date:
April 23, 2013
Source:
Max Planck Institute of Quantum Optics
Summary:
Researchers have succeeded in generating flashes of extreme ultraviolet radiation via the reflection from a mirror that moves close to the speed of light.

Picture description: A laser pulse (red, bottom), liberates electrons (green) from the carbon atoms of a nanometer-thin foil and accelerates them to close to the speed of light. An infrared light pulse impinges on the electron layer from the opposite direction and reflects off the electron mirror as a light burst in the extreme ultraviolet with a duration of only a few hundred attoseconds.
Credit: Thorsten Naeser

An international team of researchers succeeds in generating flashes of extreme ultraviolet radiation via the reflection from a mirror that moves close to the speed of light.

A dense sheet of electrons accelerated to close to the speed of light can act as a tuneable mirror that can generate bursts of laser-like radiation in the short wavelength range via reflection. A team of physicists from the Max-Planck-Institute of Quantum Optics (MPQ) in Garching, the Ludwig-Maximilians-Universitδt (LMU) Mόnchen, the Queens University Belfast (QUB) and the Rutherford Appleton Laboratory (RAL) near Oxford created such a mirror in a recent experiment. The scientists used an intense laser pulse to accelerate a dense sheet of electrons from a nanometre-thin foil to close to the speed of light and reflected a counter-propagating laser pulse from this relativistic mirror. With this experiment, the physicists managed to carry out a Gedankenexperiment (thought experiment) formulated in 1905 by Albert Einstein stating that the reflection from a mirror moving close to the speed of light could in principle result in bright light pulses in the short wavelength range. The researchers report on their results in Nature Communications, 23. April, 2013.

In everyday life, reflections of light are usually observed from surfaces that are at rest such as the reflection from a piece of glass or a smooth surface of water. But, what happens if one creates a mirror moving incredibly fast, close to the speed of light? This question was answered more than a century ago by Albert Einsteins in 1905 in his theory of special relativity. Now, an international team of researchers investigated that question in an experiment.

In the experiment conducted at the Rutherford Appleton Laboratory near Oxford the physicists irradiated a nanometre-thin, freestanding foil with a 50 femtosecond short, ultra-intense laser pulse (one femtosecond is a millionth of a billionth of a second). The impinging laser pulse liberated electrons from the carbon atoms of the foil and rapidly accelerated to close to the speed of light in less than a micrometer forming a dense sheet of electrons capable of acting as a mirror. "This mirror structure is stable for only a few femtoseconds," explains Daniel Kiefer, who wrote his Dissertation on this topic. Within this extremely short life time the scientists shot a secondary laser pulse with a wavelength in the near infrared (800 nm) and a pulse duration of several femtoseconds from the opposite direction on the generated relativistic mirror structure.

In stark contrast to a mirror at rest, light reflected from a mirror that is moving is changed in its colour (that is in its wavelength) as the reflected photons gain momentum from the mirror. This process is very similar to a ball that bounces off a racket and thereby accelerates to higher speed. However, instead of moving faster (photons already travel at the speed of light), the reflected light is shifted in its frequency. This phenomenon is very similar to the Dopplereffect observed from an ambulance siren, which sounds higher (louder) or deeper (quieter) depending on whether the ambulance is moving towards or away from the observer. In the experiment, the incredibly high velocity of the electron mirror gave rise to a change in frequency upon reflection from the near infrared to the extreme ultraviolet up to a wavelength of 60 to 80 nanometre. Moreoever, the time duration of the reflected pulses was on the order of a few hundred attoseconds only (one attosecond is a billionth of a billionth of a second).

This experiment not only supports Albert Einstein's theory of special relativity, but in fact paves the way for a new method to generate intense, attosecond short flashes of light. Those pulses would allow the electron motion in atoms to be resolved thus giving deep insight into elementary processes in nature, which are so far largely unexplored.

For Prof. Schreiber and his group at the LMU, this is only the very beginning. Our laser systems will advance in the future delivering even more powerful pulses with higher repetition rate and shorter pulse duration. This scheme will benefit strongly from those developments in laser technology and thus may enable the generation of laser-like radiation with even higher intensity and shorter wavelength ideal to explore the microcosm. "The relativistic mirror has high potential in the next years," Schreiber concludes.


Story Source:

The above story is based on materials provided by Max Planck Institute of Quantum Optics. Note: Materials may be edited for content and length.


Journal Reference:

  1. D. Kiefer, M. Yeung, T. Dzelzainis, P.S. Foster, S.G. Rykovanov, C.LS. Lewis, R.S. Marjoribanks, H. Ruhl, D. Habs, J. Schreiber, M. Zepf, B. Dromey. Relativistic electron mirrors from nanoscale foils for coherent frequency upshift to the extreme ultraviolet. Nature Communications, 2013; 4: 1763 DOI: 10.1038/ncomms2775

Cite This Page:

Max Planck Institute of Quantum Optics. "Light bursts out of a flying mirror." ScienceDaily. ScienceDaily, 23 April 2013. <www.sciencedaily.com/releases/2013/04/130423134142.htm>.
Max Planck Institute of Quantum Optics. (2013, April 23). Light bursts out of a flying mirror. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2013/04/130423134142.htm
Max Planck Institute of Quantum Optics. "Light bursts out of a flying mirror." ScienceDaily. www.sciencedaily.com/releases/2013/04/130423134142.htm (accessed October 23, 2014).

Share This



More Matter & Energy News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

3D Printed Instruments Make Sweet Music in Sweden

3D Printed Instruments Make Sweet Music in Sweden

Reuters - Innovations Video Online (Oct. 23, 2014) — Students from Lund University's Malmo Academy of Music are believed to be the world's first band to all use 3D printed instruments. The guitar, bass guitar, keyboard and drums were built by Olaf Diegel, professor of product development, who says 3D printing allows musicians to design an instrument to their exact specifications. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) — Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Jet Sales Lift Boeing Profit 18 Pct.

Jet Sales Lift Boeing Profit 18 Pct.

Reuters - Business Video Online (Oct. 22, 2014) — Strong jet demand has pushed Boeing to raise its profit forecast for the third time, but analysts were disappointed by its small cash flow. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) — As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (Oct. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins