Research team from the Technical University of Denmark achieves multi-fold increase in quantum encryption key bitrates. From their earlier research, the team’s work “achieved low and stable quantum bit error rate” – a key challenge in quantum computing research and development. The team developed protocols maximizing multi-core optic fiber; in turn, they accomplished encoding greater amounts of information thus improving quantum key distribution throughput rates. Continued progress based on single-photon arrays is expected to produce improved data-rate through efficient protocols and scalable processes. Research has also continued into photon-pair generation with multi-mode “fiber optics and four-wave mixing.” Photon-pair generation has direct application to quantum communications.
“Experimental setup: BPF: bandpass filter, SMF: single-mode fiber SI-FMF step-index few-mode fiber, BSF: bandstop filter, DM dichroic mirror, M: mirror, SPDs: single-photon detector. Inserted images show the idler in the LP01 mode, the signal in the LP02 mode, and the pump in a combination of the LP01 and LP02 modes.” (Image courtesy Technical University of Denmark under CC by 4.0)
Reference is found here at STRN… The original work is found at npj [PDF]…
See mdpi.com for the May, 2018, study on photon-pair generation in fibers…