Featured Research

from universities, journals, and other organizations

Nebraska Team First To Observe Kapitza-Dirac Effect; Could Lead To Extremely Accurate Measuring Devices

Date:
September 19, 2001
Source:
University Of Nebraska, Lincoln
Summary:
The luminous green lasers in Herman Batelaan's laboratory at the University of Nebraska-Lincoln are more than just pretty. They are the critical element in Batelaan's team becoming the first to observe the Kapitza-Dirac effect, an accomplishment that could make possible measuring devices that are thousands of times more accurate than those in use today.

Lincoln (Neb.) -- The luminous green lasers in Herman Batelaan's laboratory at the University of Nebraska-Lincoln are more than just pretty. They are the critical element in Batelaan's team becoming the first to observe the Kapitza-Dirac effect, an accomplishment that could make possible measuring devices that are thousands of times more accurate than those in use today.

Related Articles


The Kapitza-Dirac effect is the diffraction of a beam of particles, electrons in particular, by a standing wave of light. It was predicted in 1933 by a pair of future Nobel Prize winners, Russian Peter Kapitza (1894-1984) and Englishman P.A.M. Dirac (1902-84), but the technology needed to demonstrate it didn't exist at the time, and wouldn't until well after the laser was invented in 1960.

Early lasers weren't capable of producing the Kapitza-Dirac effect and it wasn't until April 11, 2001, when it was observed for the first time in Batelaan's lab in NU's Behlen Laboratory for Physics.

The confirmation was reported by Batelaan and his team of Daniel Freimund and Kayvan Aflatooni in the Sept. 13 issue of Nature, the international weekly journal of science. Freimund, the lead author of the Nature article, a doctoral candidate under Batelaan, earned his bachelor's degree in mechanical engineering and his master's in physics at Nebraska. Aflatooni, who was a post-doctoral researcher in Batelaan's lab at the time of the discovery, earned his bachelor's, master's and doctoral degrees in physics at Nebraska and now is an assistant professor of physics at Fort Hays (Kan.) State University.

A basic physics experiment that illustrates the wave nature of light involves placing a screen with two slits in it at a distance from a point source of light and placing a second screen beyond the first. Instead of two bars of light appearing on the second screen directly in line with the light and the slits, multiple light bars appear across the second screen. That's because the slits diffract the light and the bars mark the convergence of light waves. It's Quantum Mechanics 101.

Batelaan and his team in essence repeated that experiment in April, except they used an electron beam instead of a light beam and substituted a laser beam for the slitted screen. They saw that the electrons were diffracted by the laser, just as Kapitza and Dirac had predicted 68 years earlier.

Scientists have long used diffraction of optical, acoustic and radio waves in interferometers, devices that among other things measure very small distances and thicknesses. They're also used as rotation sensors in the avionics systems of airplanes. And now that Batelaan and his team have shown that particle waves can also be diffracted, Batelaan said it's possible that particle waves can be used to make a much more accurate interferometer.

"The average wavelength in a laser beam is one micron (one-millionth of a meter), which is 1 percent of the thickness of a human hair," Batelaan said. "The wavelength of this electron wave, because the electrons also have a wave, is 10,000 times smaller. That's the size of one atom.

"If you use the Kapitza-Dirac effect multiple times, you can make an interferometer. But we haven't done that yet. We're trying to figure out what the implications are for use in rotation sensors and electromagnetic field sensors."

Batelaan and his team observed the Kapitza-Dirac effect with funding from the Research Corp. A $350,000 grant received in July from the National Science Foundation will help start the search for an electron wave interferometer. Batelaan said he's excited about the possibilities of the ongoing research, but that doesn't keep him from savoring his team's discovery.

"The effect was predicted in 1933 and we were the first ones to observe it - and that's kind of nice," he said, sitting in his office beneath portraits of Kapitza and Dirac. "There were four attempts in the 1960s, but they all failed. If someone had tried it in the '90s, they would have pulled it off, so in a sense we're a bit lucky. But, hey, you need luck."


Story Source:

The above story is based on materials provided by University Of Nebraska, Lincoln. Note: Materials may be edited for content and length.


Cite This Page:

University Of Nebraska, Lincoln. "Nebraska Team First To Observe Kapitza-Dirac Effect; Could Lead To Extremely Accurate Measuring Devices." ScienceDaily. ScienceDaily, 19 September 2001. <www.sciencedaily.com/releases/2001/09/010919074443.htm>.
University Of Nebraska, Lincoln. (2001, September 19). Nebraska Team First To Observe Kapitza-Dirac Effect; Could Lead To Extremely Accurate Measuring Devices. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2001/09/010919074443.htm
University Of Nebraska, Lincoln. "Nebraska Team First To Observe Kapitza-Dirac Effect; Could Lead To Extremely Accurate Measuring Devices." ScienceDaily. www.sciencedaily.com/releases/2001/09/010919074443.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Obama: Better Ways to Create Jobs Than Keystone Pipeline

Obama: Better Ways to Create Jobs Than Keystone Pipeline

AFP (Dec. 19, 2014) US President Barack Obama says that construction of the Keystone pipeline would have 'very little impact' on US gas prices and believes there are 'more direct ways' to create construction jobs. Duration: 00:47 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:

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