Fermilab dedicates new state-of-the-art building honoring scientist Helen Edwards

Batavia, Ill., Dec. 5, 2025 — Fermi National Accelerator Laboratory hosted a building dedication ceremony today for the Helen Edwards Engineering Research Center with officials from the U.S. Department of Energy, state and local officials, and national partners in attendance. They joined the Fermilab community in unveiling the building’s official name that commemorates Dr. Helen Edwards’ pioneering research. The new building is the lab’s largest purpose-built lab and office space since the lab’s iconic Wilson Hall was completed in 1974.

Edwards was a renowned accelerator physicist best known for her work at Fermilab, including the design and operation of the Tevatron. The Tevatron held the title of the world’s most powerful particle collider for over 25 years and enabled the discoveries of the top quark in 1995 and the tau neutrino in 2000 — two of the three fundamental particles first discovered at Fermilab.

“Dr. Edwards’ scientific work is a symbol of the pioneering spirit of U.S research. Her contributions to the Tevatron and the lab helped the United States become a world leader in the study of elementary particles. We honor her legacy today by naming this research center after her as Fermilab continues shaping the next generation of research using AI, ML and quantum physics,” said Dr. Darío Gil, the under secretary for science at the U.S. Department of Energy.

The Helen Edwards Engineering Research Center is an 80,000-square-foot, multi-story laboratory and office building adjacent to Fermilab’s iconic Wilson Hall. It is a collaborative laboratory where engineers, scientists and technicians tackle the technical challenges of particle physics and pioneer groundbreaking advancements. Together, they are designing, building and testing technologies across several areas of research, including neutrino science, particle detectors, quantum science, electronics, application-specific integrated circuit development, and more.

The building boasts operational efficiencies and supports the ongoing research and planning for the premier international experiment hosted by Fermilab, the Deep Underground Neutrino Experiment (DUNE), aligned with DOE’s goal of unleashing American innovation.

In addition to traditional workspaces like offices and conference rooms, the center features cleanrooms, vibration-sensitive labs and cryogenic facilities where the components of the near detector for DUNE will be assembled and tested. The spaces are designed to be reconfigurable and adaptable to future projects.

Crews finished the construction of the building in the fall of 2022. The Helen Edwards Engineering Research Center connects to Wilson Hall, the 16-story high-rise named after Fermilab founding director Robert Wilson. The engineering center was funded by the Department of Energy’s Science Laboratory Infrastructure program and is intended to meet current and future needs for research performed at Fermilab for the DOE Office of Science.

Quantum information science and technology is an increasing priority for the U.S. Department of Energy’s Fermi National Accelerator Laboratory. As part of this goal, Fermilab is marking a major moment in quantum science this week as it hosts Exploring the Quantum Universe — A Fermilab Quantum Symposium on Dec. 4–5. Highlighting the growth of QIS research across the lab, the event also marks the launch of SQMS 2.0, the next phase of the Superconducting Quantum Materials and Systems Center, one of five national quantum information science research centers funded by the Department of Energy. The event brings together leaders from across the global quantum community to reflect on recent progress and outline next steps for the field.

The symposium comes during the International Year of Quantum Science and Technology and emphasizes the increasing push by researchers, institutions and government agencies to accelerate advances in QIS. Supported by the Department of Energy’s Office of Science, SQMS is entering its second five-year phase with renewed focus on superconducting materials, cryogenics and quantum technologies that can drive the next wave of computing, communication and sensing.

“This event is not only a celebration, it is a moment to take stock of how far we’ve come and to look boldly toward what comes next,” said Anna Grassellino, director of the SQMS Center. “The conversations happening here, the ideas, the collaborations — they will help shape the quantum technologies of the future.”

Fermilab is advancing the frontiers of QIS through cutting-edge research, technology development and partnerships that connect fundamental physics with real-world impact. From pioneering superconducting quantum computing technologies to building quantum networks and sensors, Fermilab leverages its world-class expertise and facilities to accelerate progress across the quantum ecosystem. Tools first developed for particle accelerators now support some of the world’s most coherent and stable quantum devices. By adapting accelerator-grade systems for quantum research, Fermilab and SQMS are helping pave the way for high-performance quantum systems needed for future scientific breakthroughs.

Speakers include experts from the Department of Energy, academia and industry, emphasizing that broad collaboration will advance U.S. leadership in quantum research. Organizers expect more than 600 attendees from over 100 organizations to attend.

“Quantum information science is one of the most promising and important frontiers in modern research,” said DOE Under Secretary for Science Darío Gil, who is delivering the symposium’s public lecture. “Through the cutting-edge research being performed by the SQMS Center and other research areas at Fermilab, we are seeing how deep scientific collaboration can accelerate progress and deliver real impact for society.”

Fermilab quantum research efforts include more than 60 partners — national laboratories, universities and technology companies. They are collaborating to improve high-coherence cavities, scalable cryogenics, materials, devices, ultra-precise sensors, quantum networks, algorithms and controls.  

“Our research in quantum information science spans the entire laboratory, drawing on strengths that have long positioned Fermilab to lead in emerging technologies,” said Young-Kee Kim, interim director of Fermilab. “By combining efforts across disciplines and partnering nationally, we are helping accelerate the breakthroughs that will shape the future of quantum science.”

As quantum science grows as a national priority, SQMS sits at the intersection of basic research and technology development. The center aims to advance new materials and devices, build a 100-qudit superconducting quantum processor at Fermilab and test scalable designs for future quantum data centers. Quantum systems could reshape fields from materials science to dark matter searches, and progress in coherence, fabrication and design will influence how quickly those discoveries emerge.

With attendees from across the country and around the world, the symposium reflects the energy behind the next era of quantum science — and Fermilab’s role in helping drive it. For more information, visit the event webpage: Exploring the Quantum Universe.

Scientists are closing the door on one explanation for a neutrino mystery that has plagued them for decades.

An international collaboration of scientists working on the MicroBooNE experiment at the U.S. Department of Energy’s Fermi National Accelerator Laboratory announced that they have found no evidence for a fourth type of neutrino. The paper was published today in Nature.

Earlier physics experiments saw neutrinos behaving in a way inconsistent with the Standard Model of particle physics. Theorists have suggested that a sterile neutrino could explain those anomalies. However, with this new result, MicroBooNE has been able to rule out a single sterile neutrino explanation with 95% certainty.

The Standard Model is the best theory scientists have for explaining how the universe works. However, it is incomplete.

“We know that the Standard Model does a great job describing a host of phenomena in the natural world,” said Matthew Toups, Fermilab senior scientist and co-spokesperson for MicroBooNE. “And at the same time, we know it’s incomplete. It doesn’t account for dark matter, dark energy or gravity.”

So, physicists are on the hunt for new physics that may shed light on some of the biggest mysteries in the universe.

Neutrinos are tantalizing particles when it comes to searches for new physics because so many questions surround these ghostly particles. One mystery in particular has haunted physicists for decades.

According to the Standard Model there are three types, or flavors, of neutrino: muon, electron and tau. Neutrinos oscillate between these flavors, changing, for instance, from a muon neutrino to an electron neutrino or to a tau neutrino. Scientists have been studying how neutrinos oscillate between these flavors for decades, giving them a strong foundation for understanding how often neutrinos are supposed to change flavor.

It’s really exciting to be doing both cutting-edge science that has a major impact on our field as well as developing novel techniques that will support and enable future scientific measurements.

The first suggestion that something unexpected may be occurring when neutrinos oscillate was observed by the Liquid Scintillator Neutrino Detector (LSND) at Los Alamos National Laboratory in 1995. Fermilab’s MiniBooNE experiment was initiated to verify those results. Both LSND and MiniBooNE made observations suggesting that muon neutrinos were oscillating into electron neutrinos over shorter distances than are possible with only three neutrino flavors.

“They saw flavor change on a length scale that is just not consistent with there only being three neutrinos,” explained Justin Evans, professor at the University of Manchester and co-spokesperson for MicroBooNE. “And the most popular explanation over the past 30 years to explain the anomaly is that there’s a sterile neutrino.”

Although neutrinos aren’t known for being particularly social particles, they do occasionally interact with matter via the weak force. For there to be an undiscovered neutrino it would have to be even less interactive. In the case of a sterile neutrino, this hypothetical particle would only interact via gravity.

“MicroBooNE is finally closing the chapter on one of the strongest explanations over the past few decades for those anomalies,” said Nitish Nayak, a postdoctoral research associate at Brookhaven National Laboratory and collaborator on the MicroBooNE experiment.

MicroBooNE, a liquid-argon time projection chamber experiment, sits along the Booster Neutrino Beam (BNB), just 70 meters in front of where MiniBooNE measured the anomaly. From that position, MicroBooNE observed neutrino interactions from the BNB and from another neutrino beam at Fermilab, NuMI. MicroBooNE collected data from 2015 to 2021.

“MicroBooNE is the first experiment that has done a sterile neutrino search with one detector and two beams simultaneously,” said Sergey Martynenko a research associate at Brookhaven Lab and collaborator on the MicroBooNE experiment.

Observing neutrinos from both beams reduced the uncertainties in MicroBooNE’s result, making it possible to exclude nearly the entire favored region in which a single sterile neutrino could be hiding.
“It’s really exciting to be doing both cutting-edge science that has a major impact on our field as well as developing novel techniques that will support and enable future scientific measurements,” said Toups.

In addition to continuing to search for new physics, the MicroBooNE collaboration is providing insight into how neutrinos interact in liquid argon, an important metric that will benefit other liquid-argon time projection chamber experiments such as the Deep Underground Neutrino Experiment.

Although one explanation for the anomalies seen by MiniBooNE and LSND has been ruled out, the mystery still remains.

This result used just 60% of MicroBooNE’s total data set and scientists are already beginning to sift through the rest. And MicroBooNE isn’t the only collaboration on the case.

The Short-Baseline Neutrino Program adds a powerful multi-detector approach with a near detector and a far detector to determine whether a more complicated model could explain the LSND and MiniBooNE anomalies. ICARUS, the far detector in the program, began taking beam data at Fermilab in 2021 and the Short-Baseline Near Detector (SBND) started data in 2024.

“Any time you rule out one place where physics beyond the Standard Model could be, that makes you look in other places,” said Evans. “This is a result that is going to really spur a creative push in the neutrino physics community to come up with yet more exciting ways of looking for new physics.”

This press release was originally posted by the Department of Energy on November 24, 2025.

Editor’s note:
The US Department of Energy’s Fermi National Accelerator Laboratory is at the forefront of developing artificial intelligence algorithms to drive advancements in science and society. Through the Genesis Mission, Fermilab will help reimagine the scientific process using AI to accelerate scientific discovery.

“Fermilab’s dedication to world-class research is rooted in using AI and machine learning in solving the mysteries of matter, energy, space and time. This has allowed us to accelerate our innovation capacity in quantum and particle physics research,” said Fermilab interim director Young-Kee Kim. “We are excited to play a significant role in the Genesis AI Initiative and help lead in a new age of American discovery science.”

In coordination with the DOE’s mission to advance artificial intelligence, Fermilab aims to transform discovery science by advancing quantum-computing paradigms, which will deepen our understanding of the laws of nature and the cosmos. From our world-class accelerator complex and the Deep Underground Neutrino Experiment to cutting-edge quantum devices and innovative microelectronics, Fermilab builds and operates some of the most complex scientific endeavors in the world.

Our researchers have wide-ranging expertise in AI-enabled sensing, serving massive AI-ready data sets with a deep understanding of the underlying physics and instruments. These advancements push the boundaries of technology, driving innovation that leads to broader societal impacts.

President Trump today issued an Executive Order to launch the Genesis Mission, a historic national effort led by the Department of Energy. The Genesis Mission will transform American science and innovation through the power of artificial intelligence (AI), strengthening the nation’s technological leadership and global competitiveness.

The ambitious mission will harness the current AI and advanced computing revolution to double the productivity and impact of American science and engineering within a decade. It will deliver decisive breakthroughs to secure American energy dominance, accelerate scientific discovery, and strengthen national security.

“Throughout history, from the Manhattan Project to the Apollo mission, our nation’s brightest minds and industries have answered the call when their nation needed them,” said U.S. Secretary of Energy Chris Wright. “Today, the United States is calling on them once again. Under President Trump’s leadership, the Genesis Mission will unleash the full power of our National Laboratories, supercomputers, and data resources to ensure that America is the global leader in artificial intelligence and to usher in a new golden era of American discovery.”

The announcement builds on President Trump’s Executive Order Removing Barriers to American Leadership In Artificial Intelligence and advances his America’s AI Action Plan released earlier this year—a directive to remove barriers to innovation, reduce dependence on foreign adversaries, and unleash the full strength of America’s scientific enterprise.

Secretary Wright has designated Under Secretary for Science Darío Gil to lead the initiative. The Genesis Mission will mobilize the Department of Energy’s 17 National Laboratories, industry, and academia to build an integrated discovery platform.

The platform will connect the world’s best supercomputers, AI systems, and next-generation quantum systems with the most advanced scientific instruments in the nation. Once complete, the platform will be the world’s most complex and powerful scientific instrument ever built. It will draw on the expertise of roughly 40,000 DOE scientists, engineers, and technical staff, alongside private sector innovators, to ensure that the United States leads and builds the technologies that will define the future.

The Genesis Mission will focus on addressing three key challenges of national importance:  

• American energy dominance: The Genesis Mission will accelerate advanced nuclear, fusion, and grid modernization using AI to provide affordable, reliable, and secure energy for Americans.
• Advancing discovery science: Through DOE’s investment and collaboration with industry, America is building the quantum ecosystem that will power discoveries—and industries—for decades to come.
• Ensuring national security: DOE will create advanced AI technologies for national security missions, deploy systems to ensure the safety and reliability of the U.S. nuclear stockpile, and accelerate the development of defense-ready materials.

Under Secretary for Science and Genesis Mission Director, Dr. Darío Gil: “The Genesis Mission marks a defining moment for the next era of American science. We are linking the nation’s most advanced facilities, data, and computing into one closed-loop system to create a scientific instrument for the ages, an engine for discovery that doubles R&D productivity and solves challenges once thought impossible.”  

Administrator of the National Nuclear Security Administration, Brandon Williams: “The Genesis Mission represents the next great chapter and an unparalleled opportunity for America’s scientific and national security leadership. Building on decades of innovation and collaboration across our national laboratories, NNSA will leverage AI, quantum computing, and advanced data analytics that will strengthen our deterrents and ensure the United States maintains an unmatched strategic edge over our adversaries. Under President Trump’s leadership, this mission will embody the very best of American ingenuity, turning science and innovation into security.” 

Chair of the National Laboratory Directors’ Council, Dr. John Wagner: “DOE’s National Laboratories are engines of discovery that keep the United States competitive and secure. The Genesis Mission unlocks the full potential of these institutions by giving our scientists and engineers tools to work at the speed of innovation. Our laboratories have always risen to meet the nation’s greatest challenges, and this initiative ensures we continue that legacy in the age of artificial intelligence.” 

Editor’s note: This press release was originally posted by the Department of Energy Office of Technology Commercialization. Fermilab began developing the Quantum Instrumentation Control Kit (QICK) in 2021. QICK’s use has expanded, reaching a community of about 500 users, primarily at U.S. national labs, in academia and industry. Partnering with Qblox will facilitate a new way to distribute QICK to a much wider audience in the U.S, including universities and industry, and bolster the quantum computing workforce.
The QICK team at Fermilab will continue scientific development of the tool, while Qblox will take on new workforce development, training and support.

The U.S. Department of Energy’s (DOE) Office of Technology Commercialization today announced a partnership between Fermi National Accelerator Laboratory (Fermilab) and Qblox to manufacture and distribute the Quantum Instrumentation Control Kit (QICK) in the United States, a platform for advancing quantum research and building a high-tech workforce. Facilitated by DOE’s Office of Technology Commercialization, this effort marks an important step in advancing U.S. capabilities in quantum computing, sensing, and networking.

Developed by Fermilab, QICK is an open-source platform for managing quantum readouts and controls. It plays a critical role in synchronizing quantum processors and sensors, making it a foundational technology for the growing quantum ecosystem. 

Through the partnership, Qblox, a leader in control and readout electronics that bridge quantum and classical systems, will coordinate QICK manufacturing, distribution, and supply chain operations in the United States. “This partnership demonstrates how DOE’s National Laboratories and private industry can work together to accelerate the commercialization of quantum technologies while strengthening U.S. manufacturing and workforce capabilities,” said Energy Department

Under Secretary for Science Dr. Darío Gil. “By supporting the transition of QICK from research to production, we are laying the groundwork for scalable, interoperable quantum systems that serve national and scientific priorities.”

“This collaboration underscores Qblox’s commitment to open-source developments and advancing the U.S. quantum ecosystem through workforce development and innovation” said Qblox Founderand CEO, Niels Bultink. “Qblox is proud to facilitate this Made-in-the-USA platform to strengthen America’s quantum infrastructure, cultivate a highly skilled talent pool, and cement the nation’s position as a global leader in quantum technology.”

The collaboration is being launched through a Letter of Intent between Fermilab and Qblox, with plans to formalize under a Cooperative Research and Development Agreement (CRADA) and full licensing arrangement in the coming weeks.

Together, DOE, Fermilab, and Qblox are creating a scalable model for public-private collaboration — one that ensures key elements of the quantum supply chain are developed and built domestically.

The U.S. Department of Energy Office of Science has renewed the Superconducting Quantum Materials and Systems Center (SQMS), hosted by Fermi National Accelerator Laboratory, with $125 million over the next five years to accelerate breakthroughs in quantum information science. The total planned funding is $125 million over five years, with $25 million in the first year and future funding contingent on congressional appropriations.

SQMS, founded in 2020, is one of five DOE National Quantum Information Science Research Centers created under the National Quantum Initiative Act. The center is rooted in Fermilab’s expertise in superconducting radio-frequency (SRF) cavities, materials and cryogenics — technologies originally developed for particle accelerators — and in the lab’s mission to explore the universe at its most fundamental level.

The investment from DOE Office of Science continues to unite more than 300 experts from 43 partner institutions across national laboratories, universities and industry to advance the next generation of quantum computing, communication and sensing technologies.

“In just five years, SQMS has transformed fundamental understanding into tangible progress — from record-setting coherence times to new materials and devices that redefine what’s possible in quantum technology,” said Anna Grassellino, director of the SQMS Center. “This renewal allows us to build on that foundation and take the next leap: moving from discovery to deployment. Together with our partners across national labs, universities and industry, we’re poised to scale quantum systems to a level that will unlock powerful new tools for science, technology and society.”

SQMS will build on major achievements from its first five years to develop world-leading computational capabilities, scalable and resilient quantum systems and technologies that strengthen U.S. scientific and energy leadership.

Pushing the limits of quantum performance

The center strategically complements these strengths through a multidisciplinary collaboration spanning quantum information science, superconductivity, materials science, cryogenics, microwave engineering, computational science and high-energy physics. Together, the team has tackled one of the field’s greatest challenges — extending quantum coherence, the time a qubit can reliably hold information.

Through innovations in materials, fabrication and cavity-based architectures, SQMS has achieved world-leading coherence times and developed the building blocks for its 3D-cavity, qudit-based platforms. The center has also driven progress in quantum sensing, producing record sensitivities and novel methods for dark-matter searches and precision measurements.

Entering a new era

In the next phase, SQMS will use ultra-high-coherence SRF cavities and scalable cryogenics to address some of quantum technology’s most significant hurdles. The program’s goals focus on three major efforts:

Chip-based materials and device breakthroughs

SQMS will pursue new materials and fabrication methods to deliver progressively higher-coherence superconducting devices for cavity-based computing, communication and sensing systems. The center aims to achieve the ambitious goal of 10-millisecond coherence in chip-based transmon qubits — a milestone that will also benefit commercial platforms such as those of SQMS partner Rigetti Computing.

“The SQMS collaboration is driving major progress in understanding the microscopic origins of decoherence in superconducting circuits and detectors,” said Jim Sauls, professor and Hearne Chair of Theoretical Physics at Louisiana State University. “That knowledge not only advances quantum information science, it also deepens our understanding of superconductivity, one of the most fascinating and fundamental states of matter.”

Development of a 100-plus-qudit SRF quantum processor at Fermilab

While most efforts rely on 2D superconducting qubits, SQMS is advancing a 3D cavity-based qudit approach, in which each cavity encodes multiple quantum states. This architecture offers higher connectivity, reduced control complexity and more efficient algorithm implementation. SQMS will build and deploy, in collaboration with partners such as Quantum Machines, a 100-qudit prototype — equivalent in computational space to roughly 500 qubits — within a single dilution refrigerator. The platform will serve as a unique facility for computing and sensing experiments.

Demonstration of the first scalable quantum data-center unit

To enable future quantum data centers with thousands of qubits, SQMS will prototype the cryogenic and microwave infrastructure required for large-scale interconnection. This includes high-fidelity, cavity-based links between multiple IBM quantum networking units and a liquid-helium cryoplant-based, energy-efficient solution for future quantum data centers developed with Maybell Quantum Industries.

“Fermilab and the SQMS Center are pushing the frontiers of cavity science and technology in ways that directly complement IBM’s efforts to scale quantum computing,” said Jay Gambetta, Director of IBM Research and IBM Fellow. “Their work on high-coherence superconducting cavities will ultimately help lay the foundation for the quantum computing internet, where multiple quantum computers operate together as one system, and interface with a network of other quantum computers, communication and sensors. Our initial ambition is to show we can entangle two cryogenic separated quantum computers within the next five years. This kind of collaboration is essential to move the entire field forward — from individual computers to large-scale, interconnected quantum systems that can transform discovery and industry alike.”

Advancing discovery with quantum information science

SQMS breakthroughs will open new frontiers in both technology and science. Planned experiments using SQMS-developed hardware include quantum-sensing searches for dark matter and gravitational waves, precision magnetometry and fundamental tests of quantum mechanics, along with simulations relevant to high-energy and condensed-matter physics. 

“INFN is proud to be part of the SQMS collaboration, which unites scientists across continents in the pursuit of the development of quantum technologies which are fundamental for the future of research and of our society,” said Antonio Zoccoli, president of Italian National Institute of Nuclear Physics (INFN). “By combining the strengths of the Italian community in superconducting materials, cryogenics and fundamental physics, we are accelerating progress toward a deeper understanding of nature and new technologies that will benefit society.” 

Through this renewed partnership, Fermilab and its collaborators will continue pushing the limits of quantum coherence, scaling and control — shaping the foundation for the next generation of quantum information science and technology. 

“The SQMS Center exemplifies how DOE’s national labs bring together multidisciplinary teams to tackle grand scientific challenges,” said Young-Kee Kim, interim director of Fermilab. “Its advances will help secure U.S. leadership in the global race to develop practical quantum technologies.” 

SQMS collaborators and partners

SQMS new era collaborators include: Aalto University, Ames National Laboratory, Applied Materials, Bluefors, DESY – Deutsches Elektronen-Synchrotron, Fermi National Accelerator Laboratory, IBM, Illinois Institute of Technology, Illinois Mathematics and Science Academy, Infleqtion, INFN – Istituto Nazionale di Fisica Nucleare, Johns Hopkins University, Kyocera, Lawrence Livermore National Laboratory, Lockheed Martin, Louisiana State University, Maybell Quantum Industries, NASA Ames Research Center, NIST, National Physical Laboratory, New York University, Northern Illinois University, Northwestern University, NVIDIA, Quantum Machines, Rigetti Computing, Royal Holloway University London, Rutgers University, Stanford University, Temple University, Unitary Foundation, University of Arizona, University of Colorado Boulder, University of Glasgow, University of Illinois Chicago, University of Maryland, University of Minnesota, University of Oregon, University of Pisa, University of Southern California, University of Toronto, University of Waterloo and the Universities Space Research Association. The other National QIS Research Centers funded by the DOE Office of Science are the Co-design Center for Quantum Advantage, Quantum Science Center, Quantum Systems Accelerator and Q-NEXT.

Imagine a future where networks of entangled photons, harnessing the unique properties of quantum physics, enable computing and technologies beyond anything we know today.

Researchers at the U.S. Department of Energy’s Fermi National Accelerator Laboratory and the California Institute of Technology are using a special kind of light — called “squeezed light” — they believe can overcome key challenges in building scalable quantum networks.

The cutting-edge research represents essential progress toward building a quantum network that could transform scientific research by connecting powerful quantum computers.

These networks rely on entangled qubits — pairs of quantum bits that share information across distances. In quantum physics, entanglement occurs when two or more particles become linked in such a way that what happens to one affects the other, even if they are far apart.

Researchers are working to generate and distribute entangled qubits across longer distances to build larger quantum networks. However, quantum networks over fiber optic cable face challenges such as signal loss, memory decoherence, and delays inherent to communication technologies widely used today.

A new study led by Fermilab shows the potential of a quantum network protocol that can overcome these challenges by using squeezed light, a special state of light with reduced noise and enhanced sensitivity, to pick up faint signals. This research marks a first step toward increasing the entanglement generation rate, which is a key requirement for large-scale quantum networks.

Scientists use various methods to encode qubits with quantum information. One approach uses photons — packets of light energy that have both wave and particle properties — that scientists prepare in special ways to manipulate and control qubits.

The new method described in the study uses two optical encoding types. The combination helps overcome the weaknesses of each and significantly increases the rate of entangled pair generation over long distances.

To transfer entanglement from one pair of qubits to another, scientists use a process called entanglement swapping. Unlike traditional methods that produce only one entangled pair per swap, squeezed light allows many qubits to become entangled.

“The greater number of entangled pairs per light signal, the greater the entanglement distribution efficiency,” said Alexandru Macridin, a scientist at Fermilab who led this research. “But since entangled qubits readily decay, the entanglement generation rate is very important when you build this kind of thing. The more you create, the better.”

Using the new technique, scientists generate entangled pairs by preparing light at two distant locations. Both light sources are sent to a central site equidistant between them and routed through a beam splitter that separates them into two beams of light, one transmitted and one reflected. The light beams return to the central location, where they recombine and are measured. The laws of quantum mechanics dictate that measurement destroys the light but leaves multiple pairs of long-distance entangled qubits.

The method’s effectiveness depends on the strength of the squeezing, but current technology limits how much can be squeezed.

“I calculated that producing one extra entangled pair requires three decibels of squeezing,” explained Macridin. “This means that no more than three or four entangled qubit pairs can be produced using current technology because it only allows for squeezing up to 15 decibels of light.”

Going forward, the team will explore ways to reduce light loss and other effects from fiber optic cables. They will also work to improve the technology and compare light squeezing with other methods for generating multiple qubits. This research is part of a larger collaborative project led by Fermilab called the Advanced Quantum Network, or AQNET. Funded by the Department of Energy Office of Science Advanced Scientific Computing Research program, AQNET aims to connect a local quantum network at Fermilab with quantum nodes at Argonne National Laboratory, Northwestern University, and the University of Illinois at Urbana-Champaign using optical fiber. The ultimate goal is to build a nationwide quantum network.

“With AQNET, we are now at the stage of our development where our network connections can reach metropolitan-scale distances with fiber optics,” said Fermilab scientist Cristián Peña, who leads the project. “This new protocol is another step toward that goal.”

So far, Macridin and his colleagues have confirmed that the new protocol can improve entanglement distribution efficiency in ideal laboratory settings.

The protocol is also significant because it builds on existing entanglement swapping hardware developed at Fermilab. The hardware can be readily integrated into a wide range of applications, including quantum repeaters — devices that extend quantum entanglement over longer distances and support the development of diverse quantum network designs.

Fermi National Accelerator Laboratory is America’s premier national laboratory for particle physics and accelerator research. Fermi Forward Discovery Group manages Fermilab for the U.S. Department of Energy Office of Science. Visit Fermilab’s website at www.fnal.gov and follow us on social media.