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."
The research, Robust Nodal Structure of Landau Level Wave Functions Revealed by Fourier Transform Scanning Tunneling Spectroscopy, was published in the journal Physical Review Letters.
University of Warwick: http://www.warwick.ac.uk
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
The patron animal of quantum theory poses for a unique portrait in which the camera and the sitter don't share a single photon – except by entanglement
The magnitude-6.0 quake that hit California's Napa Valley wasn't the "big one", but it loaded stress on to the Hayward fault close to the Bay Area
NASA explains what the Curiosity rover photographed on Mars after UFO blog raises questions
Bardarbunga, a subglacial stratovolcano, showing increased seismic activity; 2010 eruption caused air travel chaos
A coffee entrepreneur claims his brew is different — and better — than the trendy civet poop coffee. And it starts with the idea that elephants, unlike humans or civets, are herbivores.
Structural colours are more visible and vivid than those that use pigments as many examples from the natural world demonstrate. But sometimes pure white is what is required
Dutch biologist Ingrid van der Meer often meets with disbelief when she talks about her work on dandelions and how it could secure the future of road transport.
Pretend for a minute that it’s 1875 and you’re a mining engineer whose job it is to figure out how much gold is in them thar hills. Get it wrong, and your company is going to waste a lot of time and money hunting for gold that’s not there—or worse yet, miss out on the mother lode
It can only switch from black to transparent and back again, but that's a start
What happens when you add folds to materials that are only a few atoms thick? Several scientists set out to find the answer — and discovered that these nano-wrinkles can be quite useful.