4D quantum encryption encodes data in light particles that reach the recipient instantly after being sent, making the data inaccessible to cyber criminals.
As computer performance is constantly increasing, current encryption algorithms will soon no longer offer sufficient protection against cyber crime. However, encoding data using light particles is currently considered to be unhackable, meaning that this could become the encryption method of the future. It has now been possible to send an encrypted message with more than one bit per photon outside of a laboratory for the first time. The data was transferred over a distance of 300 meters between two house roofs in Ottawa, Canada, proving that 4D quantum encryption is suitable for everyday use.
Whereas in conventional 2D quantum encryption each light particle is encoded with either a one or a zero and therefore transfers one bit, the 4D process can manage two bits at once. This is because the photons can be coded as 00, 01, 10 or 11. This speeds up the data transfer rate immensely, as even coding one letter requires eight bits. During testing, 4D quantum encryption could transfer approximately 1.6 times more data per light particle than the 2D process. This means that the recipient obtains the information almost instantly after it has been sent — even over long distances.
4D quantum encryption as a basis for a global communication network
“This could potentially link Earth with satellites” says Ebrahim Karimi, who led the data transfer experiment. Together with his colleagues from the University of Ottawa, he wanted to prove that 4D quantum encryption functions even when influenced by the interference present in a metropolis. Despite air turbulence and electromagnetic radiation, the scientists managed to achieve an error rate of only 11 percent during their experiment. Secure data transfer only becomes impossible at 19 percent. In comparison to 2D encryption, the 4D transfer was also much more tolerant to interference, therefore meaning that it was more secure.
This means that a worldwide communication network based on 4D quantum encryption may be developed. This network may be able to reach locations in which it is not financially viable to install fiber optic cables. As the satellites required for the network would orbit at great altitude, the scientists would like to conduct further experiments over greater distances. There are plans for three test stations, 5.6 kilometers apart. “Our long-term goal is to implement a quantum communication network with multiple links but using more than four dimensions while trying to get around the turbulence,” explains Alicia Sit, a member of the research team.