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 August 20, 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 August 20, 2014).

Share This




More Matter & Energy News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) — Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) — Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) — Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) — A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 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