In Brief

23 October 2014

Quantum internet could cross seas by container ship


SIGN here for your quantum delivery. Quantum networks are super secure, but so far they only cover short distances. Extending this to a sort of quantum internet seems like a technological feat – but sending data by container ship could be the solution.

Quantum communications are especially useful because the laws of physics mean any attempt to intercept them will be detected. Recent, city-wide quantum networks can send secure data this way, but extending the range would require “quantum repeaters” – and no one knows how to build them.

Now, Simon Devitt of Ochanomizu University in Tokyo and his colleagues say we can bypass the challenges of putting repeaters on the seabed and still create a kind of international quantum internet by loading container ships with quantum data (


Depending on how the information was stored, a fully loaded vessel on a 20-day voyage from Japan to the US would be equivalent to a transfer rate of between 10 bytes per second and 1 terabyte per second.