Featured Research

from universities, journals, and other organizations

New way to measure electron pair interactions

Date:
February 11, 2014
Source:
American Institute of Physics (AIP)
Summary:
Measuring electron pair emission measurements has always been difficult because it was traditionally done using highly expensive synchrotron light sources, which are available in only a few laboratories worldwide. Now a team of researchers has developed a new way to measure the emission of electron pairs directly by combining two common laboratory instruments called time-of-flight spectrometers.

A view inside the photoemission chamber, "Hydra," shows the entry point for one time-of-flight electron spectrometer (on the left, opposite the larger open round hole), as well as a second time-of-flight electron spectrometer (on the left front side looking toward the sample, which is a round silver crystal covered by an ultrathin layer of nickel oxide).
Credit: M.Huth/Max Planck

Shoot a beam of light or particles at certain special materials and you will liberate electrons -- pairs of them -- a phenomenon known as "electron pair emission, " which can reveal fundamental properties of the solid and reveal information necessary to design novel materials for future applications.

Measuring electron pair emission has always been difficult, however, because they were traditionally done using highly expensive synchrotron light sources, which are available in only a few laboratories worldwide. Nobody has found a way to routinely measure electron pair interactions on a standard lab bench.

Now a team led by researchers at the Max Planck Institute of Microstructure Physics in Halle, Germany has done just that. They developed a new way to measure the emission of electron pairs directly by combining two common laboratory instruments called time-of-flight spectrometers, a setup they describe in the journal Applied Physics Letters, which is produced by AIP Publishing.

"Einstein received the Nobel Prize for his explanation of the photoelectric effect, which was published in 1905. Einstein considered the possibility that the photon energy can be transferred to more than one electron," explained Michael Huth, a postdoctoral researcher at the Max Planck Institute of Microstructure Physics. "The existence of this process provides direct access to the electron correlation strength."

An electron pair is "excited" by a single photon; from an experimental point of view, this requires the combination of a suitable light source and electron spectrometers.

Developing such a setup involved "a significant effort," according to Huth. Comically, the team dubbed their setup's photoemission chamber "Hydra," because its two time-of-flight spectrometers give the chamber an appearance of having multiple heads.

As a proof-of-principle experiment, the team chose to investigate nickel oxide (NiO), which, in theory, should have strong electron correlation effects. While measuring the energy distribution, they were surprised to discover that in contrast to the metal, the energy sum of the electron pair shows no prominent features.

What's the significance? "Our observation is that metals and nickel oxide behave very differently," Huth said. "This implies that our technique allows us to quantify the electron correlation strength."

Quantifying a solid-state material's electron correlation strength is important because it allows researchers to characterize its useful properties, including superconductivity, metal-insulator transition and long-range magnetic ordering. "Our experimental data will guide theory toward understanding the fundamental properties of solids, and one day help to design novel functional materials," Huth noted.

Next, the researchers' sights are set on exploring different materials to gain a more complete picture of electron correlation by running experiments at different photon energies. "We also plan to optimize the efficiency and stability of our new setup for ongoing experiments," Huth said.

The article, "Electron pair emission detected by time-of-flight spectrometers: Recent progress" by Michael Huth, Cheng-Tien Chiang, Andreas Trόtzschler, Frank O. Schumann, Jόrgen Kirschner, and Wolf Widdra appears in the journal Applied Physics Letters.


Story Source:

The above story is based on materials provided by American Institute of Physics (AIP). Note: Materials may be edited for content and length.


Journal Reference:

  1. Tsubasa Funabashi, Jun Mizuno, Masamichi Sato, Masao Kitajima, Makoto Matsuura, Shuichi Shoji. Film of lignocellulosic carbon material for self-supporting electrodes in electric double-layer capacitors. APL Materials, 2013; 1 (3): 032104 DOI: 10.1063/1.4820430

Cite This Page:

American Institute of Physics (AIP). "New way to measure electron pair interactions." ScienceDaily. ScienceDaily, 11 February 2014. <www.sciencedaily.com/releases/2014/02/140211144157.htm>.
American Institute of Physics (AIP). (2014, February 11). New way to measure electron pair interactions. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2014/02/140211144157.htm
American Institute of Physics (AIP). "New way to measure electron pair interactions." ScienceDaily. www.sciencedaily.com/releases/2014/02/140211144157.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) — 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) — Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) — Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) — Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
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