Researchers are achieving sustained, high-fidelity quantum teleportation

A viable quantum internet – a network in which information stored in qubits is shared through entanglement over long distances – would transform the fields of data storage, precision detection and computing and usher in a new era of communication.

This month, scientists at the Fermi National Accelerator Laboratory – a US Department of Energy national laboratory affiliated with the University of Chicago – together with partners from five institutions, took an important step towards realizing a quantum internet.

In a paper published in PRX Quantum, the team presents for the first time a demonstration of a sustained long-range teleportation of qubits made of photons (particles of light) with greater than 90% reliability.

The qubits were teleported over a 44-kilometer fiber optic network using state-of-the-art single-photon detectors and standard equipment.

“We are excited about these results,” said Fermilab scientist Panagiotis Spentzouris, head of the Fermilab quantum science program and one of the paper’s co-authors. “This is a significant achievement towards building a technology that will redefine the way we conduct global communications.”

The achievement comes just a few months after the US Department of Energy revealed its blueprint for a national quantum internet at a press conference at the University of Chicago.

Linking particles

Quantum teleportation is a “bodiless” transfer of quantum states from one location to another. The quantum teleportation of a qubit is achieved by means of quantum entanglement, where two or more particles are inseparably linked. If an entangled pair of particles is shared between two separate locations, regardless of the distance between them, the encoded information is teleported.

The joint team – researchers from Fermilab, AT&T, Caltech, Harvard University, NASA Jet Propulsion Laboratory and University of Calgary – successfully teleported qubits on two systems: the Caltech Quantum Network and the Fermilab Quantum Network. The systems are designed, built, commissioned and implemented by Caltech’s public-private research program on Intelligent Quantum Networks and Technologies, or IN-Q-NET.

“We are very proud to have reached this milestone in sustainable, high-performing and scalable quantum teleportation systems,” said Maria Spiropulu, the Shang-Yi Ch’en professor of physics at Caltech and director of the IN-Q-NET research program. . . “Results will be further improved with system upgrades that we expect to complete in the second quarter of 2021.”

Both the Caltech and Fermilab networks, which offer near-autonomous data processing, are compatible with both existing telecommunications infrastructure and emerging quantum processing and storage equipment. Researchers use them to improve the reliability and speed of entanglement, with an emphasis on complex quantum communication protocols and fundamental science.

“With this demonstration, we begin to lay the groundwork for the construction of a metropolitan quantum network in Chicago,” said Spentzouris.

The Chicagoland network, called the Illinois Express Quantum Network, is being designed by Fermilab in collaboration with Argonne National Laboratory, Caltech, Northwestern University and industry partners.

“This achievement is a testament to the success of the collaboration between disciplines and institutions that are so important to what we achieve in science,” said Joe Lykken, assistant director of research at Fermilab. “I commend the IN-Q-NET team and our partners in academia and industry for this first of its kind in quantum teleportation.