Researchers at the Australian National University have developed a new data storage architecture that could be used to store quantum information as well as connect to traditional fiber optics. This design could be fundamental in the construction of a global network for quantum computers, the so-called quantum Internet.
The study, published in Nature Physics, used erbium atoms – a type of rare Earth material – inside a crystal. This set-up can store quantum information for more than one second, which is 10,000 times longer than current devices. It also uses the same bandwidth of fiber optics, so it can directly interface with current networks.
“We have shown that an erbium-doped crystal is the perfect material to form the building blocks of a quantum Internet that will unlock the full potential of future quantum computers," said associate professor Matthew Sellars in a statement. "The effort to build a quantum computer is often described as the space race of the 21st century. Our work will allow us to build a global network to connect quantum computers."
Quantum computers rely on the constructions of qubits, the quantum mechanical equivalent of bits. So far, these are quite delicate and can be easily disrupted, so researchers are struggling to both maintain them and transmit them with high fidelity. The erbium crystal makes it easier for qubits to be transferred as they go through less hassle.
"At the moment researchers are using memories that don't work at the right wavelength, and have to employ a complicated conversion process to and from the communications wavelength," explained Dr Rose Ahlefeldt. "This can be inefficient, and means they have to do three very difficult things instead of just one."
Currently, the record for longest distance quantum communication is held by the Chinese quantum satellite Micius, which was able to use quantum teleportation across 1,400 kilometers (870 miles). Through fiber optics or air, the record is around 100 kilometers (62 miles).
Quantum computers hold the promise to revolutionize many fields of science, since they have the ability to process problems that the most advanced supercomputers can’t. The field has gone through some incredible breakthroughs in the last decade, but it’s still early days for this technology. There are challenges ahead, but researchers are rising to them.