Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > First Demonstration of 'Spin-Orbit Coupling' in Ultracold Atomic Gases

In an ultracold gas of nearly 200,000 rubidium-87 atoms (shown as the large humps) the atoms can occupy one of two energy levels (represented as red and blue); lasers then link together these levels as a function of the atoms’ motion. At first atoms in the red and blue energy states occupy the same region (Phase Mixed), then at higher laser strengths, they separate into different regions (Phase Separated).
Credit: Ian Spielman, JQI/NIST
In an ultracold gas of nearly 200,000 rubidium-87 atoms (shown as the large humps) the atoms can occupy one of two energy levels (represented as red and blue); lasers then link together these levels as a function of the atoms’ motion. At first atoms in the red and blue energy states occupy the same region (Phase Mixed), then at higher laser strengths, they separate into different regions (Phase Separated).
Credit: Ian Spielman, JQI/NIST

Abstract:
Physicists at the Joint Quantum Institute (JQI) have for the first time caused a gas of atoms to exhibit an important quantum phenomenon known as spin-orbit coupling. Their technique opens new possibilities for studying and better understanding fundamental physics and has potential applications to quantum computing, next-generation "spintronics" devices and even "atomtronic" devices built from ultracold atoms.

First Demonstration of 'Spin-Orbit Coupling' in Ultracold Atomic Gases

Gaithersburg, MD | Posted on March 21st, 2011

The JQI is a collaboration of the National Institute of Standards and Technology (NIST) and the University of Maryland-College Park.

One of the most important phenomena in quantum physics, spin-orbit coupling describes the interplay that can occur between a particle's internal properties and its external properties. In atoms, it usually describes interactions that only occur within an atom: how an electron's orbit around an atom's core (nucleus) affects the orientation of the electron's internal bar-magnet-like "spin." In semiconductor materials such as gallium arsenide, spin-orbit coupling is an interaction between an electron's spin and its linear motion in a material.

In the researchers' demonstration of spin-orbit coupling, two lasers allow an atom's motion to flip it between a pair of energy states. The new work, published in Nature,* demonstrates this effect for the first time in bosons, which make up one of the two major classes of particles. The same technique could be applied to fermions, the other major class of particles, according to the researchers. The special properties of fermions would make them ideal for studying new kinds of interactions between two particles—for example, those leading to novel "p-wave" superconductivity, which may enable a long-sought form of quantum computing known as topological quantum computation.

In an unexpected development, the team also discovered that the lasers modified how the atoms interacted with each other and caused atoms in one energy state to separate in space from atoms in the other energy state. This promises to lead to useful experimental techniques.

"Spin-orbit coupling is often a bad thing," said JQI's Ian Spielman, senior author of the paper. "Researchers make ‘spintronic' devices out of gallium arsenide, and if you've prepared a spin in some desired orientation, the last thing you'd want it to do is to flip to some other spin when it's moving."

"But from the point of view of fundamental physics, spin-orbit coupling is really interesting," he said. "It's what drives these new kinds of materials called ‘topological insulators.'"

One of the hottest topics in physics right now, topological insulators are special materials in which location is everything: the ability of particles to flow depends on where they are located within the material. They may lead to useful devices. While researchers have been making higher and higher quality versions of this special class of material in solids, spin-orbit coupling in trapped ultracold gases of atoms could help realize topological insulators in their purest, most pristine form, as gases are free of impurity atoms and the other complexities of solid materials.

* Y.-J. Lin, K. Jiménez-García and I.B. Spielman. Spin-orbit-coupled Bose-Einstein condensates. Nature. Posted online March 2, 2011.

####

For more information, please click here

Contacts:
Ben Stein
(301) 975-3097

Copyright © NIST

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 Links

“JQI Physicists Demonstrate Coveted ’Spin-Orbit Coupling’ for the First Time in Ultracold Atomic Gases”

Related News Press

News and information

Carbon nanoballs can greatly contribute to sustainable energy supply January 27th, 2015

The laser pulse that gets shorter all by itself: Ultrashort laser pulses have become an indispensable tool for atomic and molecular research; A new technology makes creating short infrared pulses easy and cheap January 27th, 2015

New pathway to valleytronics January 27th, 2015

Stomach acid-powered micromotors get their first test in a living animal January 27th, 2015

Entanglement on a chip: Breakthrough promises secure communications and faster computers January 27th, 2015

Physics

New pathway to valleytronics January 27th, 2015

Visualizing interacting electrons in a molecule: Scientists at Aalto University and the University of Zurich have succeeded in directly imaging how electrons interact within a single molecule January 26th, 2015

Spintronics

Piezoelectricity in a 2-D semiconductor: Berkeley Lab researchers discovery of piezoelectricty in molybdenum disulfide holds promise for future MEMS December 22nd, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

'Giant' charge density disturbances discovered in nanomaterials: Juelich researchers amplify Friedel oscillations in thin metallic films November 26th, 2014

Quantum Computing

New pathway to valleytronics January 27th, 2015

Entanglement on a chip: Breakthrough promises secure communications and faster computers January 27th, 2015

Graphene brings quantum effects to electronic circuits January 22nd, 2015

Improved interface for a quantum internet January 16th, 2015

Discoveries

Carbon nanoballs can greatly contribute to sustainable energy supply January 27th, 2015

The laser pulse that gets shorter all by itself: Ultrashort laser pulses have become an indispensable tool for atomic and molecular research; A new technology makes creating short infrared pulses easy and cheap January 27th, 2015

New pathway to valleytronics January 27th, 2015

Stomach acid-powered micromotors get their first test in a living animal January 27th, 2015

Announcements

Industrial Nanotech, Inc. Announces New OEM Customer January 27th, 2015

Carbon nanoballs can greatly contribute to sustainable energy supply January 27th, 2015

The laser pulse that gets shorter all by itself: Ultrashort laser pulses have become an indispensable tool for atomic and molecular research; A new technology makes creating short infrared pulses easy and cheap January 27th, 2015

New pathway to valleytronics January 27th, 2015

Quantum nanoscience

New pathway to valleytronics January 27th, 2015

Graphene brings quantum effects to electronic circuits January 22nd, 2015

Nano-beaker offers insight into the condensation of atoms January 21st, 2015

Atoms can be in 2 places at the same time: Researchers of the University of Bonn have shown that cesium atoms do not follow well-defined paths January 20th, 2015

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 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE