New milestone reached in quantum teleportation
Sustained Long-Distance Quantum Teleportation Achieved For First Time
A QUANTUM COMPUTING CONCEPT. METAMORWORKS/SHUTTERSTOCK.COM
Quantum computers are hailed as the future of computing, with the allure of faster, more secure, and massively advanced capabilities ushering in a rapid increase in the quantum market over the past decade.
Now, researchers from a collaboration of technology companies are claiming to have completed the first successful long-distance quantum teleportation, a breakthrough that could pave the way for the quantum internet to become reality. Their results were published in PRX Quantum.
“We’re thrilled by these results,” said Panagiotis Spentzouris, head of the Fermilab quantum science program and one of the paper’s co-authors in a statement.
But what is a quantum computer and the quantum internet?
Well, first we need to understand how traditional computers work before we can delve into their space-age cousins. Computers work by using inputs called bits, that are either ‘on’ or ‘off’, which are assigned the numbers ‘1’ or ‘0’. From these inputs, a computer can process a massive number of calculations rapidly, and by stuffing more switches into a computer chip that can be either 1 or 0, you can increase the processing power of the computer chip.
Now, let’s introduce quantum states into the mix. Quantum particles are tricky little particles that can exist in three states compared to the standard two. In a computer, these can be either 1, 0, or both at the same time (called superposition). These represent a different type of input called qubits, and they make up the foundation of quantum computing.
To achieve a full quantum internet, these qubits must be transported over long distances from one device to another, much like how ‘normal’ internet works. But as with everything quantum, the movement of data is much more complicated than simply passing it down an ethernet cable.
The researchers wanted to achieve quantum teleportation, a feat in which qubits are passed through state-of-the-art fiber networks using entanglement. Quantum particles have a strange ability to be linked to each other, becoming ‘entangled’ together. If the entangled pair of particles is split between two different locations, it is possible to transmit information between them – theoretically over a long distance. However, a number of issues have prevented quantum teleportation from becoming a reality. For example, one theory states that you cannot copy quantum information exactly (the no-cloning theorem), and so transmission over distance may be unreliable.
By using off-the-shelf technology, the researchers were finally able to complete long-distance quantum teleportation. They successfully transmitted qubits over a distance of 44 kilometers (27.3 miles) with a fidelity (how ‘exact’ the information is) of 90%, a feat no company has been able to achieve previously. The researchers believe this is a massive step towards the future of computing and communication.
A quantum internet would be a game-changer for the world of technology as we know it, with data moving faster, more secure, and possibly impossible to steal. The movement from conventional computers to quantum computers is a dream of many researchers, and it is looking increasingly likely this will become reality.
There is still a way to go before a quantum internet is a viable reality. Quantum particles are still extremely difficult to study and measure, and the fidelity must also be improved before reliable data transmission can occur. Alongside that, such a network is almost certainly going to be extremely expensive and therefore not viable for the majority of networks in the near future, but we can dream. Despite this, achieving quantum teleportation is an extremely promising step forward.
“We are very proud to have achieved this milestone on sustainable, high-performing and scalable quantum teleportation systems,” said Maria Spiropulu, Shang-Yi Ch’en professor of physics at Caltech and director of the IN-Q-NET research program, in a statement.
“The results will be further improved with system upgrades we are expecting to complete by Q2 2021.”