Quantum physics is increasingly being touted as relevant and significant for the world of technology. Researchers have been trying to find ways to embed it deeper into technology because quantum communication, if made possible, can be the most secure method of relaying information from one place to another.
One of the problems with using quantum mechanics in communications is that the moment anyone reads the data relayed as quantum signals, the data is destroyed. It is based on Heisenberg’s uncertainty principle which states that the action of a viewer viewing a particle changing its state.
However, Chinese researchers claim that they have been able to overcome this problem. The researchers say that they have made use of two techniques to solve this conundrum: the first technique is superposition which allows a quantum particle to exist in multiple states. And the second principle that is being used is that of entanglement, which is a queer property which lets the two particles influence each other and remain related no matter how great the distances are among them.
The researchers contained the routing information within the polarisation of a photon. First, a single photon is emitted which has both vertical and horizontal polarisation. This is then converted into a pair of entangled photons. So when they reach the router, the router reads the polarisation of one of these photons to determine where the other will go.
According to a post on MIT blog, “The new router has significant limitations. The most significant of these is that it can handle only one quantum bit or qubit at a time. And because the process of parametric down conversion cannot handle more qubits, it cannot be scaled to more qubits. That’s a significant drawback. It means that this is a proof-of-principle device but not one that will ever form the basis of a future quantum internet.”
Source: Cornell University Library