Envisioning a quantum internet capable of safely transferring information globally via photons in various quantum states is one thing; establishing its practicability is a huge hurdle. Harvard physicists have done exactly that by utilizing existing telecommunications fiber in the Boston area. Their achievement is a ground-breaking demonstration of the longest fiber distance between two quantum memory nodes yet achieved.
Advances in quantum information storage are accelerating progress toward the creation of a worldwide quantum internet. This achievement presents the promise of secure communication over long distances, possibly hundreds or thousands of kilometers. A quantum internet, as opposed to the traditional internet, which transmits digital bits—0s and 1s—via electrical or optical signals, uses quantum bits instead.
These qubits leverage the peculiar quantum phenomenon of entanglement, wherein particles become interconnected, so that measuring one particle instantaneously impacts the state of another, regardless of the physical separation between them. Such technology could revolutionize communication by enabling unhackable transmissions and facilitating the interconnection of quantum computers.
The landmark work, published in Nature, was led by Mikhail Lukin, the Joshua and Beth Friedman University Professor in the Department of Physics, in collaboration with Harvard professors Marko Lončar and Hongkun Park, members of the Harvard Quantum Initiative, as well as researchers at Amazon Web Services.