Quantum Entanglement

Researchers from the Commerce Department's National Institute of Standards and Technology (NIST) have coaxed six atoms into spinning together in two opposite directions at the same time, a phenomenon that physicists call a Schrödinger "cat" state which obeys the unusual laws of quantum physics. [click here to see animation]

The researchers "entangled" six beryllium ions, or charged ions, so that their nuclei were all spinning clockwise and counterclockwise at the same time. Entanglement occurs when the quantum properties of two or more particles are correlated--that is, if a change occurs in one particle, it will be reflected in the other particles. Albert Einstein called this "spooky action at a distance."

The NIST work beats the previous record of five entangled particles of light, called photons.

The NIST work also demonstrates another quantum property known as "superposition," the ability for a particle to exist in two states at once. The beryllium ions were placed in the most extreme superposition of spin states possible with six ions since they were all spinning in one direction and the opposite direction simultaneously.

Entanglement and superposition are being exploited in laboratories around the world in the development of new technologies such as quantum computers.

The finding was detailed in the Dec. 1 issue of the journal Nature.