Featured Research

from universities, journals, and other organizations

Physicists explain the collective motion of particles called fermions

Date:
March 29, 2012
Source:
University at Buffalo
Summary:
Scientists generally believed that certain collective behavior appeared in fermions only when they moved in unison at very long wavelengths. Now, however, collective behavior has been discovered at short wavelengths in one Fermi system, helium-3.

Some people like company. Others prefer to be alone. The same holds true for the particles that constitute the matter around us: Some, called bosons, like to act in unison with others. Others, called fermions, have a mind of their own.

Related Articles


Different as they are, both species can show "collective" behavior -- an effect similar to the wave at a baseball game, where all spectators carry out the same motion regardless of whether they like each other.

Scientists generally believed that such collective behavior, while commonplace for bosons, only appeared in fermions moving in unison at very long wavelengths. Now, however, collective behavior has been discovered at short wavelengths in one Fermi system, helium-3.

A team led by Professor Eckhard Krotscheck -- a physicist who recently joined the University at Buffalo from the Johannes Kepler University in Linz, Austria -- predicted the existence of the behavior using theoretical tools. Independently, but practically at the same time, a French team observed the collective behavior.

A paper detailing both the theoretical and experimental discoveries appeared in the journal Nature on March 29.

Krotscheck said the scientists' success in developing accurate theoretical predictions lay, in part, in the fact that they focused on mathematical tools instead of trying to reproduce experiments.

"Knowing how nature ticks at a microscopic scale, we set out to develop a robust theory that was capable of dealing with a wide range of situations and systems," Krotscheck said. "We demanded that our mathematical description is accurate for both fermions and bosons, in different dimensions, and for both coherent and incoherent excitations. Only after we were done, we looked at experiments."

Krotscheck's colleagues on the study include Henri Godfrin, Matthias Meschke and Ahmad Sultan of the Institut NΓ©el, CNRS, and UniversitΓ© Joseph Fourier in France; Hans-Jochen Lauter of the Institut Laue-Langevin in France and Oak Ridge National Laboratory; and Helga Bohm and Martin Panholzer of the Institute for Theoretical Physics at Johannes Kepler University in Austria. Meschke also belongs to the Low Temperature Laboratory of Aalto University in Finland.


Story Source:

The above story is based on materials provided by University at Buffalo. Note: Materials may be edited for content and length.


Journal Reference:

  1. Henri Godfrin, Matthias Meschke, Hans-Jochen Lauter, Ahmad Sultan, Helga M. Bφhm, Eckhard Krotscheck, Martin Panholzer. Observation of a roton collective mode in a two-dimensional Fermi liquid. Nature, 2012; 483 (7391): 576 DOI: 10.1038/nature10919

Cite This Page:

University at Buffalo. "Physicists explain the collective motion of particles called fermions." ScienceDaily. ScienceDaily, 29 March 2012. <www.sciencedaily.com/releases/2012/03/120329171605.htm>.
University at Buffalo. (2012, March 29). Physicists explain the collective motion of particles called fermions. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2012/03/120329171605.htm
University at Buffalo. "Physicists explain the collective motion of particles called fermions." ScienceDaily. www.sciencedaily.com/releases/2012/03/120329171605.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA's First 3-D Printer In Space Creates Its First Object

NASA's First 3-D Printer In Space Creates Its First Object

Newsy (Nov. 26, 2014) — The International Space Station is now using a proof-of-concept 3D printer to test additive printing in a weightless, isolated environment. Video provided by Newsy
Powered by NewsLook.com
Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Bolivian Recycling Initiative Turns Plastic Waste Into School Furniture

Reuters - Innovations Video Online (Nov. 26, 2014) — Innovative recycling project in La Paz separates city waste and converts plastic garbage into school furniture made from 'plastiwood'. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Blu-Ray Discs Getting Second Run As Solar Panels

Blu-Ray Discs Getting Second Run As Solar Panels

Newsy (Nov. 26, 2014) — Researchers at Northwestern University are repurposing Blu-ray movies for better solar panel technology thanks to the discs' internal structures. Video provided by Newsy
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) — Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
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:

More Coverage


Neutrons Uncover New Density Waves in Fermion Liquids

Mar. 29, 2012 — Scientists discover zero-sound mode oscillations in super-chilled helium. Scientists have carried out the first investigation of two-dimensional fermion liquids using neutron scattering, and ... read more

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