Featured Research

from universities, journals, and other organizations

Quantum physics: First images of Landau levels revealed

Date:
October 1, 2012
Source:
University of Warwick
Summary:
Physicists have directly imaged Landau Levels – the quantum levels that determine electron behavior in a strong magnetic field – for the first time since they were theoretically conceived of by Nobel prize winner Lev Landau in 1930.

Experimentally Measured Landau Level 1.
Credit: Image courtesy of University of Warwick

Physicists have directly imaged Landau Levels -- the quantum levels that determine electron behaviour in a strong magnetic field -- for the first time since they were theoretically conceived of by Nobel prize winner Lev Landau in 1930.

Using scanning tunnelling spectroscopy -- a spatially resolved probe that interacts directly with the electrons -- scientists at institutions including the University of Warwick and Tohoku University have revealed the internal ring-like structure of these Landau Levels at the surface of a semiconductor.

The experimental challenge in the work was to have sufficient spatial resolution in order to overcome the intrinsic disorder in the material which usually only allows the observation of smeared out "drift" states.

The images clearly show that Landau was right when he predicted that, in a clean system, the electrons would take on the form of concentric rings, the number of which increase according to their energy level.

This simple counting behaviour forms the basis of the so-called quantum Hall effect.

While originally of mostly fundamental interest, the effect has in recent years been used to define the standard for what we mean by electrical resistance and could soon be employed to define the kilogram as well.

Professor Rudolf Roemer of the Department of Physics at the University of Warwick said: "This is an exciting step for us, we are really seeing for the first time individual quantum mechanical wave functions of electrons in real materials.

"On the face of it this might seem far removed from everyday life.

"However the question of what defines a kilogram is currently being debated, with the spacing between the rings of these Landau levels acting as a kind of marker for a universal weight.

"So next time you measure out your sugar to bake a cake, you might unknowingly be making use of these quantum rings."


Story Source:

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


Journal Reference:

  1. K. Hashimoto, T. Champel, S. Florens, C. Sohrmann, J. Wiebe, Y. Hirayama, R. Rφmer, R. Wiesendanger, M. Morgenstern. Robust Nodal Structure of Landau Level Wave Functions Revealed by Fourier Transform Scanning Tunneling Spectroscopy. Physical Review Letters, 2012; 109 (11) DOI: 10.1103/PhysRevLett.109.116805

Cite This Page:

University of Warwick. "Quantum physics: First images of Landau levels revealed." ScienceDaily. ScienceDaily, 1 October 2012. <www.sciencedaily.com/releases/2012/10/121001095441.htm>.
University of Warwick. (2012, October 1). Quantum physics: First images of Landau levels revealed. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2012/10/121001095441.htm
University of Warwick. "Quantum physics: First images of Landau levels revealed." ScienceDaily. www.sciencedaily.com/releases/2012/10/121001095441.htm (accessed September 1, 2014).

Share This




More Matter & Energy News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Australian Airlines Relax Phone Ban Too

Australian Airlines Relax Phone Ban Too

Reuters - Business Video Online (Aug. 26, 2014) — Qantas and Virgin say passengers can use their smartphones and tablets throughout flights after a regulator relaxed a ban on electronic devices during take-off and landing. As Hayley Platt reports the move comes as the two domestic rivals are expected to post annual net losses later this week. Video provided by Reuters
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) — Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Chinese Researchers Might Be Creating Supersonic Submarine

Chinese Researchers Might Be Creating Supersonic Submarine

Newsy (Aug. 26, 2014) — Chinese researchers have expanded on Cold War-era tech and are closer to building a submarine that could reach the speed of sound. Video provided by Newsy
Powered by NewsLook.com
Breakingviews: India Coal Strained by Supreme Court Ruling

Breakingviews: India Coal Strained by Supreme Court Ruling

Reuters - Business Video Online (Aug. 26, 2014) — An acute coal shortage is likely to be aggravated as India's supreme court declared government coal allocations illegal, says Breakingviews' Peter Thal Larsen. 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