Physicists at the National Institute of Standards and Technology (NIST) announce the successful teleportation of a full quantum logic operation – a set of computer circuit instructions – between two separated electrically charged atoms (commonly known as ions). This could offer an exciting glimpse into the future of quantum computing.
Quantum teleportation involves sending data from one ion to a completely separate one. Previous attempts at quantum teleportation were limited to data fragments, but the NIST team have managed to teleport an entire quantum logic operation.
NIST physicist Dietrich Leibfried says: “We verified that our logic operation works on all input states of two quantum bits with 85 to 87% probability — far from perfect, but it is a start.”
Quantum Computers & Qubits
Quantum teleportation of logic operations could be an effective way to conduct operations between qubits – quantum bits – thus allowing for the development of quantum computers.
The research team managed to transfer a quantum controlled-NOT (CNOT) logic operation – or logic gate – from one beryllium ion qubit to another, across a distance of over 340 micrometers – a distance large enough to rule out significant direct interaction. The CNOT operation dictated that, if the first qubit is 1, the second is flipped from 0 to 1 or vice versa.
Quantum entanglement – a process that links the quantum properties of separated particles – was achieved in 95% of the cases, with the full logic operation transfer succeeding 85% to 87%.
“Gate teleportation allows us to perform a quantum logic gate between two ions that are spatially separated and may have never interacted before,” Leibfried says. “The trick is that they each have one ion of another entangled pair by their side, and this entanglement resource, distributed ahead of the gate, allows us to do a quantum trick that has no classical counterpart.”
“The entangled messenger pairs could be produced in a dedicated part of the computer and shipped separately to qubits that need to be connected with a logic gate but are in remote locations,” Leibfried continues.
In addition to quantum data teleportation, the research also integrated other essential operations for building quantum computers, such as different ion type control, ion transport, and subset-limited entangling operations.
The research was supported by the Office of the Director of National Intelligence, the Intelligence Advanced Research Projects Activity and the Office of Naval Research.