Better memory

Physicists at the

(NIST) have used charged atoms (ions) to demonstrate a quantum physics version of computer memory lasting longer than 10 seconds--more than 100,000 times longer than in previous experiments on the same ions.

The advance improves prospects for making practical, reliable quantum computers, which make use of the properties of quantum systems rather than transistors for performing calculations or storing information.

Quantum computers, if they can be built, could break today's best encryption systems, accelerate database searching, develop novel products such as fraud-proof digital signatures or simulate complex biological systems to help design new drugs.

As described in the August 5, 2005, issue of Physical Review Letters, NIST scientists stored information in single beryllium ions for longer periods of time by using a different pair of the ions' internal energy levels to represent 1 and 0 than was used in the group's previous quantum computing experiments. This new set of quantum states is unaffected by slight variations in magnetic fields, which previously caused memory losses in ions stored in electromagnetic traps.