New Ion Trap Could Push Quantum Computing To Next Level

At age 62 now, David Wine land expects he'll be an old man--well into his 80s--before the first quantum computer is commercialized. But that's not stopping him from trying. Wineland leads a team at the National Institute of Standards and Technology that has developed a first-of-its-kind electromagnetic "trap" for ions that could be mass produced to make quantum computers for practical use.

The theory behind quantum computers is to exploit the unusual behavior of the smallest particles of matter and light. Ions--electrically charged atoms--are promising candidates for use as quantum bits, or qubits, in quantum computing. Unlike a standard computer bit, which is represented by a 0 or 1, a qubit can represent a 0 and 1 simultaneously. Therefore, the number of calculations scales exponentially with each qubit, when compared with today's standard bit. In theory, quantum computers could crack in seconds problems that today's computers take hours or longer to do. At such speeds, quantum computers could break data encryption codes and search large databases much faster than today's conventional processors.

The trap, described last month in the journal Physical Review Letters, could help researchers overcome one of the biggest obstacles in creating a quantum computer: scaling components and processes that have been successfully demonstrated in the lab. NIST's ion trap is the first in which all electrodes are arranged in a single, horizontal layer that's simpler to manufacture than older ion traps, which have two or three layers. The single-layer device can trap a dozen magnesium ions without generating too much heat from electrode voltage fluctuations, Wineland says. Heating presented a problem for earlier traps. Researchers at NIST and elsewhere hope to build single-layer traps with more complex structures.

The group Wineland heads is part of NIST's time and frequency division, which has as its main goal to develop a better atomic clock. The same research findings that advance quantum computing can be applied to making an atomic clock that's more accurate. Wineland contends an experimental atomic clock in the NIST lab that employs quantum ideas is now the world's most accurate clock. "Some of our simple ideas are already bearing fruit," he says, "so it doesn't bother me that I may never see a real factoring machine, because some of the basic ideas are already being applied."