A research team led be Andreas Wallraff from the Swiss Federal Polytechnic Institute (ETH) have successfully transferred quantum information between two qubits at the push of a button. A landmark achievement that has implications for increasing the reliability of quantum computers,
At the ETH Laboratory For Solid State Physics in Switzerland scientists first connected two superconducting qubits with a coaxial cable. The second step involves transferring the quantum state of the broadcasting qubit to an intermediary microwave photon resonator. Then from there quantum information can be relayed across the coaxial cable to a second microwave resonator where it is then transferred to the
“Our transmission rate for quantum states is among the highest ever realized, and at 80 percent, our transmission fidelity is very good in the first realization of the protocol,” says Andreas Wallraff.
Using this new technique researchers were also able to create quantum entanglement between the two qubits at 50 000 times per second whereas the transmission itself took less than a millionth of a second.
Up until now quantum computers have been chaotic and unreliable at best. In fact most of the time a transmission fails and the researchers whave to continue until it worked. However with this new coaxial method transmissions succeed 80% of the time.
Now the researchers want to make the broadcast two directional so that the recieving qubit can send information back to the transmitting qubit, a features it vital for functional quantum computers that could see wide adoption within the next couple years.
The transmission distance would also need to be increased although the team demonstrated that a super cooled coaxial cable could transfer information over a several tens of meters.
cover photo: ETH Zurich /M. Pechal, T. Walter, P. Kurpiers