10 stories
Show: Summaries / Headlines only
Security agencies in the US, UK, France, Germany, the Netherlands, Sweden, Australia, and Canada say QKD cannot replace public-key cryptography in government systems. Programs in the EU, Germany, Canada, China, Japan, Singapore, and India pay for QKD anyway.
QKD is provably secure only if its devices behave as modeled and its classical channel is already authenticated. NSA, the NCSC, and four European agencies allow it a niche role at most, citing implementation attacks, trusted relays, and cost.
IonQ and Duke researchers reported 1,032 entangled ion-memory pairs per second at 87.9% fidelity. In their preprint, they cited estimates that links between error-corrected modules need roughly 10 to 100 times that rate.
NSA kept the five limitations it listed in 2020 and added an argument that QKD security established at certification can degrade. It dropped a line saying it did not expect to certify or approve QKD products.
A Guangxi University-led team measured infrared emission from the silicon attenuators that dim light on QKD transmitter chips. In worst-case simulations, the authors calculated that the leak could cut a standard link's secure range from about 320 to 19 kilometers.
Coordinated by LuxQuanta, the six-member QUARTERNEXT consortium plans 48 months of work on continuous-variable QKD equipment and intends to provide its hardware and software for testing at Nostradamus, the EU's QKD evaluation effort.
In measurement-device-independent QKD, an untrusted relay makes every measurement, so the detector attacks demonstrated on commercial systems no longer work. Researchers have still taken full keys through a flawed transmitter. Users also give up key rate.
In a preprint, Cisco and UC Santa Barbara researchers reported 4% or less decoherence with slow switching and at least 90% fidelity at 1 MHz. Conversion between photon encodings has not yet been demonstrated.
IonQ said it linked two of its commercial trapped-ion computers at a distance in work funded in part through an Air Force Research Laboratory agreement. The company gave no fidelity, entanglement rate, or distance and cited no paper.
The researchers placed both entanglement sources in one Brooklyn building and made the swap at a Manhattan data center. They reported measured rates above 0.65 swaps per second over deployed fiber, or more than 1.5 after a detector correction.
