The Future of the Internet: Exploring Quantum Communication with Amazon and Harvard

An entangled photon has been sent between two quantum computers across 35 kilometers of optical fiber cable thanks to the creative “quantum network” built by Amazon and Harvard University. With ultra-secure and efficient data transfer promised by quantum communication, this milestone is a major step in the right direction.

A network able to record, store, and transmit data originally recorded in light was established by a group of academics from Harvard and the Amazon Web Services Center for Quantum Networking. Quantum entangled photons are used by quantum networks, in contrast to the light-based traditional Internet. To keep entanglement without changing the information, however, certain repeaters are required to stop photons from dispersing across great distances.

In their work, Harvard and AWS created experimental nodes using current nanofabrication technologies that “trap light and force it to interact with quantum memories.” In one of the tests, a photon-encoded qubit was sent to a quantum memory at Harvard. Metrics taken on one might have an impact on the other since the photon and memory become linked.

The photon performed a quantum frequency conversion, moving from a visible to a telecommunications frequency, to reduce losses during transmission over optical fiber. After passing across Harvard’s subterranean fiber network, the photon was re-converted to its original frequency. The photon next interacted with another quantum memory in a different lab, transmitting entanglement and enabling detection of the photon without disclosing the underlying quantum information when it bounced off the second memory.

The first tests revealed that the quantum entangled photon was held for more than a second and travelled over 35 kilometers, which is more than 300,000 kilometers for light. Nevertheless, AWS has said that the network still requires major enhancements before it can be used commercially because it is now sluggish and limited to sending one quantum memory at once.