Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Quantum Simulator for Complex Electronic Materials

Abb./©: Univ.-Prof. Dr. Immanuel Bloch, Institut für Physik, Universität Mainz
impression of a fermiotic Mott Insulator: the two colors indicate the different spin states of the atoms
Abb./©: Univ.-Prof. Dr. Immanuel Bloch, Institut für Physik, Universität Mainz impression of a fermiotic Mott Insulator: the two colors indicate the different spin states of the atoms

Abstract:
Researchers from Mainz, Cologne and Jülich simulate complex electronic insulator with ultracold atoms in artificial crystals of light

Quantum Simulator for Complex Electronic Materials

Germany | Posted on December 5th, 2008

The design of new materials with specific properties is an important but demanding challenge in physics and chemistry. Already in 1982 Nobel Prize winner Richard P. Feynman therefore suggested to build a "quantum simulator" in order to understand and predict the properties of complex materials by simulating them using an artificial, but highly controllable quantum system. In the latest issue of the journal Science researchers from the University of Mainz, the University of Cologne and the Forschungszentrum Jülich show how to simulate the properties of electrons in a real crystal by using ultracold fermionic atoms trapped in an artificial crystal formed by interfering laser beams - a so-called optical lattice.

The researchers succeeded in demonstrating one of the most dramatic effects of the electron-electron repulsion: When the interactions between the electrons get too strong, a metal can suddenly become insulating. The resulting so-called Mott-insulator is probably the most important example of a strongly correlated state in condensed matter physics, and it is a natural starting point for the investigation of quantum magnetism. Furthermore, high temperature superconductivity is found to arise in close proximity to it. "Atoms in an optical lattice are a nearly perfect quantum simulator for electrons in a solid, as they offer a very flexible model-system in a clean and well-controlled environment," explains Ulrich Schneider from the University of Mainz.

A direct investigation of complex materials and high temperature superconductors is difficult because of the presence of disorder and many competing interactions in the real crystalline materials. "This makes it very hard to identify the role of specific interactions and, in particular, to decide whether repulsive interactions between fermions alone can explain high temperature superconductivity." In the experiment, a gas of potassium atoms is first cooled down to temperatures near absolute zero. Subsequently, an optical lattice is formed by overlapping several laser beams. To the atoms, the resulting standing-wave field appears as a regular crystal of hundreds of thousands individual micro-traps, similar to an array of optical tweezers. The ultracold atoms, which play the role of electrons in real solids, will line up at the nodes of this standing-wave field.

By investigating the behavior of the atoms under compression and increasing interaction strength, and thereby measuring their compressibility, the experimentalists led by Prof. Immanuel Bloch of the Johannes Gutenberg University Mainz have been able to controllably switch the system between metallic and insulating states of matter and find evidence for a Mott-insulating phase within the quantum gas of fermionic atoms. In such a Mott-insulating phase, the repulsive interactions between the atoms force them to order one-by-one into the regular lattice structure. The observation of the fermionic Mott-insulator in the context of optical lattices opens up a new possibility to simulate and study strongly correlated states and related phenomena. This is affirmed by the excellent agreement achieved in comparing the experiment with theoretical calculations of modern condensed matter theory performed in Cologne and Jülich, which included extensive simulations on the Jülich based supercomputer system JUGENE.

####

For more information, please click here

Contacts:
Professor Dr Immanuel Bloch
Department of Physics
Johannes Gutenberg University
D 55099 Mainz
Tel +49 6131 39-26234
Fax +49 6131 39-25179

Copyright © Johannes Gutenberg University Mainz

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Ultrasensitive sensor using N-doped graphene July 26th, 2016

The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

XEI Scientific Partners with Electron Microscopy Sciences to Promote and Sell its Products in North and South America July 25th, 2016

Physics

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Attosecond physics: Mapping electromagnetic waveforms July 25th, 2016

Entanglement: Chaos - Researchers at UCSB blur the line between classical and quantum physics by connecting chaos and entanglement July 14th, 2016

Chemistry

New reaction for the synthesis of nanostructures July 21st, 2016

Pushing a single-molecule switch: An international team of researchers from Donostia International Physics Center, Fritz-Haber Institute of the Max Planck Society, University of Liverpool, and the Polish Academy of Sciences has shown a new way to operate a single-molecule switch July 19th, 2016

Rice's 'antenna-reactor' catalysts offer best of both worlds: Technology marries light-harvesting nanoantennas to high-reaction-rate catalysts July 18th, 2016

Discoveries

Ultrasensitive sensor using N-doped graphene July 26th, 2016

The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

Announcements

Ultrasensitive sensor using N-doped graphene July 26th, 2016

The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016

Designing climate-friendly concrete, from the nanoscale up: New understanding of concrete’s properties could increase lifetime of the building material, decrease emissions July 25th, 2016

XEI Scientific Partners with Electron Microscopy Sciences to Promote and Sell its Products in North and South America July 25th, 2016

Quantum nanoscience

Quantum drag:University of Iowa physicist says current in one iron magnetic sheet can create quantized spin waves in another, separate sheet July 22nd, 2016

A new spin on reality July 15th, 2016

Physicists couple distant nuclear spins using a single electron: For the first time, researchers at the University of Basel have coupled the nuclear spins of distant atoms using just a single electron July 12th, 2016

Quantum technologies to revolutionize 21st century: Nobel Laureates to discuss impacts at 66th Lindau Meeting July 5th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic