Magnets talk to bring quantum days closer
Australian researchers are working on one step of the process that could see quantum information teleporting around the world instantaneously.
A local team has developed a way for superconducting quantum chips to talk to each other over large distances through an optical fibre.
It is just one of the part of the quantum entanglement and teleportation puzzle – and is a key step toward building a global quantum internet using quantum repeaters.
The idea makes use of the tiny magnetic fields generated by quantum chips to alter the properties of an optical cavity, via a magnetostrictive material.
A material that is “magnetostrictive” physically expands in the presence of a magnetic field.
By using this, the team was able to show how the magnetic fields from the quantum chips can effectively speak via the optical cavity and connected optical fibre, through to a distant superconducting chip in a lab located elsewhere.
“Quantum cryptography, the secret transfer of information over optical fibres that is protected via the laws of quantum mechanics, is one application of quantum science and technology that already has commercial applications,” said Professor Jason Twamley from the ARC Centre of Excellence for Engineered Quantum Systems (EQUS) at Macquarie University.
He worked on the project along with Macquarie colleague Dr Keyu Xia and Dr Michael Vanner from the the University of Queensland.
“Superconducting quantum chips are one of the most promising areas of development to become the hardware for tomorrow’s quantum computers,” Twamley said.
“Our superconducting/optical interface will help plug these chips together over large distances.
“This and other applications, such as quantum computing, quantum teleportation and quantum sensing, would benefit greatly from the ability to connect up quantum devices over long distance, for example, if they could plug in to a quantum internet.
“Our hybrid-quantum system approach allows us to take advantage of both the power of quantum computing with superconducting circuits and existing low-loss high-speed optical telecommunications technology,” said Dr Vanner.
“It’s a very exciting direction, quantum technology certainly has a bright future,” said Dr Xia.
The paper “An opto-magneto-mechanical quantum interface between distant superconducting qubits” has been published in the journal Scientific Reports.