'Teleportation' technology paves the way for quantum computers

It's not quite "Star Trek", but researchers have teleported bits of information across a computer chip, paving the way for quantum computers.

 

Scientists at the Swiss Federal Institute of Technology (ETH) in Zurich detailed the results of the study in the journal Nature, LiveScience reported.

 

For their latest experiment, the scientists used entanglement, a property of quantum physics, to teleport quantum bits called "qubits."

 

"When two particles interact, they form a connection — they are entangled — so that an action performed on one affects the other, even when they're separated by great distances. In addition, no matter how far apart they are, if you know the state of one particle, you instantly know the state of the other," LiveScience said.

 

Benjamin Schumacher, a professor of physics at Kenyon College in Ohio, said creating such a circuit is important, adding a real quantum computer must be solid state.

 

A solid state computer has single-piece transistors and with no moving parts.

 

For his part, Bill Munro, a research scientist at Japanese phone giant NTT said the ETH team's work is a "very nice experiment."

 

Past experiments at teleportation used lasers to transport quantum information between photons, but this may not be practical for building real computers, LiveScience said.

 

However, Schumacher noted solid-state circuits are well-known, and computer chip maker have had much experience miniaturizing them.

 

Study co-author Arkady Fedorov from the University of Queensland in Australia said future experiments would likely involve getting the teleportation to work in more than one chip, using more qubits.

 

Experiment

 

In their experiment, the scientists put three micron-size electronic circuits on a computer chip measuring 0.3 by 0.3 inches.

 

Two of the circuits were the senders, while the third was the receiver. The scientists cooled the chip to near absolute zero and turned on a current in the circuits.

 

At that temperature, the qubits became entangled, and the ETH team encoded information in the form of spin states, into the sending circuits' qubits, then measured them.

 

They then measured the state of the qubits in the receiver, and found the sending and receiving qubits' states were correlated, meaning the information had been teleported.

 

Also, the ETH group made a qubit out of billions of electrons, nearly a quarter of a millimeter across.

 

"It's not anymore like a photon that you cannot see or some atom in a trap," Fedorov said.

 

Contradictory requirements

 

Schumacher said another unique aspect of their work is that for the qubits to remain in their dual state, they cannot interact with the environment, yet a computer's components have to interact with each other.

 

"You have two contradictory requirements. The qubits must interact with each other and the parts have to be isolated from the outside world," he said.

 

Big step

 

Raymond LaFlamme, executive director of the Institute for Quantum Computing at the University of Waterloo in Waterloo in Ontario, said the experiment is big because it implies teleporting not just qubits but the logical operations.

 

"You can change the transformation that you do. You can transform the bit ... and then flip the bit from 0 to 1," he said. — TJD, GMA News