Two More Steps Toward Quantum Computing

 

The first solid state quantum processor, developed at Yale
University, can perform simple algorithms.

Blake Johnson/Yale University

Quantum computing—using individual atoms as information carriers—could transform the way we study the world, solving problems that would take many human lifetimes for today’s supercomputers in a matter of days. Unlike conventional computers, which store each piece of data as a single value (either zero or one), quantum processors can take on multiple values simultaneously, which is why they are so efficient. Or rather why they would be, if we could figure out how to build them. So engineers in the field are abuzz about two major advances toward the creation of a practical quantum computer.


Researchers at the National Institute of Standards and Technology (NIST) in Colorado unveiled a device that meets the basic criteria for a scaled-up quantum computer. It can store and display data, shuttle information around the processor, and perform repeated logic operations with a consistently low error rate. “We’ve pulled all the components together for the first time,” says Jonathan Home, a physicist at NIST who leads the project. His team accomplished the feat by pairing quantum bits—in this case, super-cold beryllium atoms used to store data—with magnesium atoms that act as refrigerants. (Even a little heat makes it difficult to control the atoms.) Lasers allowed the scientists to direct the computations performed by the atoms.


Meanwhile, a separate group headed by physicist Robert Schoelkopf at Yale University has built the first solid-state quantum processor. Unlike most quantum computing systems, the structure of this device resembles that of the integrated circuits in current computers, which could help bridge the gap between today’s technology and tomorrow’s.