Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

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

Haydale Secures Exclusive Development and Supply Agreement with Tantec A/S: New reactors to be built and commissioned by Tantec A/S represent another step forward towards the commercialisation of graphene October 24th, 2014

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

MEMS & Sensors Technology Showcase: Finalists Announced for MEMS Executive Congress US 2014 October 23rd, 2014

Nanoparticle technology triples the production of biogas October 23rd, 2014

SUNY Polytechnic Institute Invites the Public to Attend its Popular Statewide 'NANOvember' Series of Outreach and Educational Events October 23rd, 2014

Chemistry

Iranian, Malaysian Scientists Study Nanophotocatalysts for Water Purification October 23rd, 2014

Physics

Solid nanoparticles can deform like a liquid: Unexpected finding shows tiny particles keep their internal crystal structure while flexing like droplets October 12th, 2014

Unconventional photoconduction in an atomically thin semiconductor: New mechanism of photoconduction could lead to next-generation excitonic devices October 9th, 2014

Nanoparticles Break the Symmetry of Light October 6th, 2014

Ultrafast remote switching of light emission October 2nd, 2014

Discoveries

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

Iranian, Malaysian Scientists Study Nanophotocatalysts for Water Purification October 23rd, 2014

Nanoparticle technology triples the production of biogas October 23rd, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

Announcements

Haydale Secures Exclusive Development and Supply Agreement with Tantec A/S: New reactors to be built and commissioned by Tantec A/S represent another step forward towards the commercialisation of graphene October 24th, 2014

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

Advancing thin film research with nanostructured AZO: Innovnano’s unique and cost-effective AZO sputtering targets for the production of transparent conducting oxides October 23rd, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

Quantum nanoscience

NIST quantum probe enhances electric field measurements October 8th, 2014

Quantum environmentalism: Putting a qubit's surroundings to good use October 2nd, 2014

Rice launches Center for Quantum Materials: RCQM will immerse global visitors in cross-disciplinary research September 30th, 2014

Big Results Require Big Ambitions: Three young UCSB faculty receive CAREER awards from the National Science Foundation September 18th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE