It's likely that you've heard that quantum entanglement - 'spooky action at a distance' as Einstein called it, seem to defy the laws of physics. The state of one particle, light years apart from another, can immediately 'define' the state of the latter particle. It feels like this breaks the laws of physics, because doesn't this then occurs at a speed greater than the speed of light?
However, this 'teleportation' is unfortunately well within the constraints of physics and no information gets passed from one particle to the next.
You can think of quantum entanglement like a pair of red and blue socks scattered around your house. If you know one sock is in the dryer and another sock is under your bed, and you look under your bed to see a red sock, then you know certainly, that the sock in the dryer is the blue one. No information actually gets passed between the socks. One sock doesn't tell the next "I'm blue, so you have to be red now." Instead, observing the first sock gives you information of the second one.
Interestingly, although no information is passed faster than the speed of light, “teleportation” has another related and useful meaning in the world of quantum computing.
So, then, what is quantum teleportation?
Classical bits are either 0 or 1. A qubit, until it's measured, is in a superposition, which can be thought of as a blended state of 0 and 1 at the same time. When two qubits interact, they can become entangled (they become a matching set of socks as discussed above) and measuring one instantly tells you something about the other, no matter how far apart they are. But until they're measured, they exist in this superposition.
In quantum teleportation, two separate computers start by sharing a pair of entangled qubits, A and B. The sender’s computer holds qubits T (the one whose 'state' we want to 'teleport') and A. The receiver only has B. The sender performs a special joint measurement on T and A, which randomly outputs two classical bits (00 / 01 / 10 / 11). That measurement completely destroys the original state of T, but it also steers B into a state that is related to T’s original state. The sender then communicates the two classical bits from the joint measurement, to the receiver with classical channels. When the receiver applies a simple correction to B based on those two bits, B becomes an exact copy of the state that T used to be. So although no physical particle has travelled between the labs faster than light, the amazing thing is that no extra copy of the state was ever made, and the original on T is gone forever.
Unfortunately, teleportation doesn’t beat the speed of light. A classical message is still needed, so instant galactic messaging is still some way away.
Why this matters for cyber and communications
Quantum teleportation is one of the building blocks of quantum networks, and recently, scientists showcased teleportation of multiple qubits across a network. Combined with quantum key distribution (QKD), this underpins ultra-sensitive links where any eavesdropping attempt leaves a detectable trace. Some go as far as to argue that this is the first step to an 'unhackable internet'.
But as the expert Dr. Rajiv Shah points out: today’s classical encryption for data in transit is already very strong, and most real-world breaches happen elsewhere. A “quantum internet” will not magically fix bad cyber hygiene.
"Nothing is ever unhackable. Even if the comms channel has guaranteed security, what about the assumptions this depends upon, hacking the endpoints etc?" - Rajiv Shah (PhD in Quantum Physics, Managing Director at MDR Security)
Instead, teleportation and QKD will, in the future, exist alongside classical tools, hardening specific high-value links rather than replacing the whole internet.
Rajiv also stresses that the real value is in distributed quantum computing.
"A big challenge is scaling up quantum computing; if we could make lots of smaller quantum computers and entangle them together this could address this challenge. That’s the real innovation here – a way of distributing multiple qubit operations across physically separate systems."
Building a huge, multi-bit quantum computer is no trivial task. 'Teleportation' will allow many smaller devices to be entangled into a larger virtual machine, so multi-qubit operations can be shared across physically separate processors.
What's Canberra’s role in this?
Canberra is already on the front line of quantum development. Although by a method other than 'teleportation', groups at ANU’s, are continuously working on quantum communication technologies. Take the Quantum Optical Ground Station for instance, this group is designing high-performance, secure laser links to low satellites, the Moon and through to deep space. ANU researchers are also developing quantum free-space adaptive optics to keep quantum signals stable through the atmosphere, which is a key step towards satellite-based QKD and scaling up quantum networks.
Through Artemis II, NASA and ANU will test laser communications that can send data 10–100 times faster than traditional radio, using cost-effective technology built here in Canberra. In the future, the same optical infrastructure could carry quantum-encrypted links between Earth, orbit and the lunar gateway.
For students, researchers and companies, quantum teleportation is an important framework to understand the implications of, especially as quantum capabilities continue progressing. It’s a gateway technology for scalable quantum computing. The research done in Canberra positions this city as the place where a quantum-ready future is being built, whilst the ongoing international partnerships and national initiatives position academics and industry members in the perfect spot to explore, and refine new use cases of these technologies.
