Of the $61 million recently announced by the U.S. Department of Energy for quantum information science studies, $17.5 million will fund research at DOE’s Oak Ridge National Laboratory. These projects will help build the foundation for the quantum internet, advance quantum entanglement capabilities — which involve sharing information through paired particles of light called photons — and develop next-generation quantum sensors.
The quantum bits, or qubits, used to encode information in quantum systems can be valued not just at 0 or 1 but also in superposition (both states combined) to enable calculations beyond the limits imposed by classical computer bits. By exploiting this unique property of quantum mechanics, scientists can probe new possibilities — from enhanced data storage and more secure communications to simulations at unprecedented scale and more accurate sensing of astral phenomena.
ORNL and DOE’s Los Alamos National Laboratory will receive $12.5 million for one of the first two DOE-funded projects focused on enabling the quantum internet. Through the Quantum-Accelerated Internet Testbed project, or QuAInT, a multidisciplinary team of computer scientists, engineers and physicists will pursue objectives determined during last year’s Quantum Internet Blueprint Workshop.
The ORNL team, which includes principal investigator and Quantum Information Science Group Leader Nicholas Peters and Wigner Fellow Joseph Lukens, will work with LANL, quantum technology company Qubitekk, Amazon Web Services, Purdue University and the University of Tennessee, Knoxville to design and deploy a quantum internet testbed capable of sending and receiving information on an intracity scale.
UTK researchers led by physics professor George Siopsis will leverage state-of-the-art superconducting single-photon nanowire detectors to house one of the nodes in this network at the university, which is a 20-mile drive from ORNL. This node will eventually be connected to nearby nodes via future optical fiber and to more distant nodes through satellite communication systems. The QuAInT project will also provide partial financial support to train three graduate students in quantum networking.
“We’re looking to leverage quantum technologies to transition from tabletop demonstrations to real-world experiments. We will take advantage of frequency multiplexing methods to parallelize and scale up these resources.”
Over the next five years, the QuAInT team will develop numerous building blocks needed to enable the testbed and, eventually, a widespread quantum internet that could provide unparalleled storage capacity and cybersecurity advantages. Key components include quantum memory capabilities being developed at Purdue and multiple types of photon sources soon to be under construction at LANL and ORNL. These resources will eventually enable the partner institutions to share quantum data using satellites in a future space program.
At ORNL, researchers will integrate these technologies into interconnected quantum networks and embed automated tuning features to account for changing environmental conditions. They will also combine quantum teleportation — a method of transferring qubits between disparate locations — and a previously developed resource called a frequency processor — which can arbitrarily transform the frequency properties of light — to take full advantage of the bandwidth available in quantum networks.
Along with collaborators at the University of Arizona, ORNL scientists, including Lukens, Nageswara Rao and Bing Qi, will improve optical networks as part of the three-year Entanglement Management and Control in Transparent Optical Quantum Networks project, which will receive $1.8 million.
These networks use light to transmit information through optical fibers — thin threads resembling clear strands of human hair. In classical optical networks, each fiber can typically carry only a few dozen different wavelengths of light because of safety concerns and transmission impairments. But with entangled photons, quantum optical networks can support additional communication channels simultaneously, which allows internet providers to distribute entanglement to users more efficiently.
Led by Peters, the team will build high-bandwidth entangled sources to test theoretical predictions, identify practical constraints and measure how much quantum information such a network can realistically carry.
“With a dedicated quantum network, we could potentially provide hundreds of optical channels for quickly carrying quantum information,” Peters said.
Finally, DOE will allocate $3.2 million over four years to ORNL and to DOE’s Lawrence Berkeley National Laboratory for the Quantum Enhanced Detection of Quantum Fields and Charged Particles project led by ORNL’s Raphael Pooser. Researchers from ORNL, LBNL, Purdue and the University of Maryland will develop sophisticated quantum sensors capable of detecting dark matter, a mysterious material widely believed to be the most abundant substance in the universe.
Using measurement techniques known as “squeezing” and back-action evasion, both of which dramatically reduce noise, these sensors could identify subtle disturbances in magnetic and gravitational fields caused by previously unobservable interactions between atoms and miniscule particles of dark matter.
“We can make classical networks of these sensors today, but we ultimately want to deploy them in quantum networks. This is moonshot-type work, with high risks and high rewards.”
This work will complement dark matter research being conducted through the Quantum Science Center, a DOE QIS Research Center headquartered at ORNL. Through these three funding awards, ORNL researchers and collaborators will combine their expertise to push the boundaries of new technologies and record the next chapter in the laboratory’s long history of quantum research.
UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.— Elizabeth Rosenthal