A research team at Wits University has discovered a way to improve data transmission across fibre networks.<\/p>\n
The team comprising of a PhD student at the university, as well as several colleagues from Wits and Huazh University of Science and Technology in Wuhan, China.<\/p>\n
This research uses quantum physics to improve data security across fibre networks without the need to replace legacy fibre infrastructure.<\/p>\n
Our team showed that multiple patterns of light are accessible through conventional optical fibre that can only support a single pattern, said Wits PhD student, Isaac Nape.<\/p>\n
We achieved this quantum trick by engineering the entanglement of two photons. We sent the polarised photon down the fibre line and accessed many other patterns with the other photon.<\/p>\n
Entanglement refers to particles interacting in a way that the quantum state of each particle cannot be described without reference to the state of others even if the particles are separated by large distances.<\/p>\n
In this scenario, the researchers manipulated the qualities of the photon on the inside of the fibre line by changing the qualities of its entangled counterpart in free space.<\/p>\n
In essence, the research introduces the concept of communicating across legacy fibre networks with multi-dimensional entangled states, bringing together the benefits of existing quantum communication with polarised photons with that of high-dimension communication using patterns of light, said team leader Wits Professor Andrew Forbes.<\/p>\n
Quantum entanglement has been explored extensively over the past few decades, with the most notable success story being increased communications security through Quantum Key Distribution (QKD).<\/p>\n
This method uses qubits 2D quantum states to transfer a limited amount of information across fibre links by using polarisation as a degree of freedom.<\/p>\n
Another degree of freedom is the spatial pattern of light, but while this has the benefit of high-dimensional encoding, it requires a custom fibre optical cable making it unsuitable to already existing networks.<\/p>\n
Our team found a new way to balance these two extremes, by combining polarisation qubits with high-dimensional spatial modes to create multi-dimensional hybrid quantum states, said Nape.<\/p>\n
The trick was to twist the one photon in polarisation and twist the other in pattern, forming spirally light that is entangled in two degrees of freedom, said Forbes.<\/p>\n
Since the polarisation entangled photon has only one pattern, it could be sent down the long-distance single-mode fibre, while the twisted light photon could be measured without the fibre, accessing multi-dimensional twisted patterns in the free-space.<\/p>\n
These twists carry orbital angular momentum (or spin), a promising candidate for encoding information.<\/p>\n<\/p>\n
<\/p>\n
Go here to see the original:<\/p>\n
Fibre on steroids Wits student uses quantum physics for massive improvements - MyBroadband<\/a><\/p>\n","protected":false},"excerpt":{"rendered":" A research team at Wits University has discovered a way to improve data transmission across fibre networks. The team comprising of a PhD student at the university, as well as several colleagues from Wits and Huazh University of Science and Technology in Wuhan, China Continue reading