Featured Research

from universities, journals, and other organizations

X-rays Have Become Laser-like

Date:
February 23, 2005
Source:
Max Planck Society
Summary:
An Austrian-German research team demonstrates for the first time a source of coherent kiloelectronvolt X-rays, which promises extraordinary applications.

The purple light originates from helium atoms excited by intense laser light. The laser pulses propagate along the axis of the purple lobes (horizontally) through the helium gas, and the X-ray beam (not visible) is radiated in a beam several hundred micrometers in diameter in the same direction.
Credit: Image : J. Seres, Vienna University of Technology

Radiologists and biologists have been dreaming - ever since the discovery of lasers - of a compact laboratory source emitting X-rays in one direction in a laser-like beam. Such a source would permit X-ray images to be recorded with far higher resolution at vastly reduced dose levels, allowing early-stage cancer diagnosis at dramatically reduced risk. Microscopes furnished with this source would make nanometer-sized biomolecules perceivable in their natural surrounding (in vivo). It may take many years before this dream comes true, but the experiment reported by an Austrian-German collaboration led by Ferenc Krausz indicates a promising way of realizing the dream some day. Researchers at Vienna University of Technology, the University of Würzburg, the University of Munich and Max Planck Institute of Quantum Optics demonstrated the first source of laser-like X-rays at a wavelength of 1 nanometer with a compact laboratory apparatus [Nature 433, 596 (2005)] in an experiment in Vienna, funded by the Austrian Science Fund.The colour of light is determined by the length of one cycle of the electromagnetic wave (referred to by physicists as the wavelength) that makes up light. Red light has a wavelength of around 700 nanometers, whereas our eye perceives radiation as violet light if its wavelength is only 400 nanometers. Light of even shorter wavelength is invisible (ultraviolet light), and with the wave cycle shortened to less than 1 nanometer, the X-ray regime is entered.

The Austrian-German team focused a sequence of intense ultrashort flashes of red light at a gas of helium atoms to convert 700-nm laser light into a 1-nm wave of X-ray light emitted by the excited atoms (Figure). The intense laser field makes the negatively charged electron cloud perform giant oscillations around the positively charged atomic core, thereby turning the atoms into antennas. Because of the giant amplitude of their oscillations, these radiate waves not only at the wavelength of the driving laser (700-nm) but also at shorter wavelengths. Since the antennas are in phase over in time, they also keep time when emitting their waves. Although these tiny "atomic" waves are extraordinarily faint, because they all oscillate in time they add to build up an X-ray wave of significant intensity delivered in a highly-directed beam parallel to the incident laser.

The phenomenon described above is not new. It has become a standard technique for routinely producing laser-like extreme ultraviolet radiation at wavelengths down to the 10 nanometer regime. Pushing the frontier of this technology to ever shorter wavelengths has proven ever more difficult because it requires atoms to be exposed to laser light of ever greater intensity, which tends to disintegrate the atoms. What makes the situation even worse, the free electrons ripped off the atoms by the strong laser field impede the buildup of an intense wave from the faint "atomic" waves.

The Vienna-Würzburg-Munich team have overcome these problems by irradiating the atoms with the world’s shortest high-intensity laser pulses, lasting merely 5 millionths of a billionth of a second (= 5 femtoseconds). These pulses hit the atoms so abruptly that they have no time to disintegrate before emitting the X-ray burst. Thanks to this extremely short interaction time, the researchers have not only managed to break the nanometer barrier but also created a source of X-ray bursts that may, for the first time, be briefer than 0.1 femtosecond (= 100 attoseconds). The X-ray beam delivered by the new source is - at present - too weak for any practical applications, but the research team are confident that technical improvements will boost the X-ray power by several orders of magnitude. Once this feat is achieved, this novel research tool will open up new prospects in several areas of physics, biology and materials science.

Original work:

J. Seres, E. Seres, A.J. Verhoef, G. Tempea, C. Streli, P. Wobrauschek, V. Yakovlev, A. Scrinzi, C. Spielmann, F. KrauszSource of coherent kiloelectronvolt X-raysNature 433, 596; 10. February 2005


Story Source:

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


Cite This Page:

Max Planck Society. "X-rays Have Become Laser-like." ScienceDaily. ScienceDaily, 23 February 2005. <www.sciencedaily.com/releases/2005/02/050222193309.htm>.
Max Planck Society. (2005, February 23). X-rays Have Become Laser-like. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2005/02/050222193309.htm
Max Planck Society. "X-rays Have Become Laser-like." ScienceDaily. www.sciencedaily.com/releases/2005/02/050222193309.htm (accessed July 29, 2014).

Share This




More Matter & Energy News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Newsy (July 28, 2014) — Stanford University published its findings for a "pure" lithium ion battery that could have our everyday devices and electric cars running longer. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) — AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) — Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) — Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
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:
from the past week

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