One of the goals of the Superconducting Quantum Materials and Systems Center is to build a beyond-state-of-the-art quantum computer based on superconducting technologies. The center also will develop new quantum sensors, which could lead to the discovery of the nature of dark matter and other elusive subatomic particles.
The U.S. Department of Energy’s Fermilab has been selected to lead one of five national centers to bring about transformational advances in quantum information science as a part of the U.S. National Quantum Initiative, announced the White House Office of Science and Technology Policy, the National Science Foundation and the U.S. Department of Energy today.
The initiative provides the new Superconducting Quantum Materials and Systems Center funding with the goal of building and deploying a beyond-state-of-the-art quantum computer based on superconducting technologies. The center also will develop new quantum sensors, which could lead to the discovery of the nature of dark matter and other elusive subatomic particles. Total planned DOE funding for the center is $115 million over five years, with $15 million in fiscal year 2020 dollars and outyear funding contingent on congressional appropriations. SQMS will also receive an additional $8 million in matching contributions from center partners.
The SQMS Center is part of a $625 million federal program to facilitate and foster quantum innovation in the United States. The 2018 National Quantum Initiative Act called for a long-term, large-scale commitment of U.S. scientific and technological resources to quantum science.
The revolutionary leaps in quantum computing and sensing that SQMS aims for will be enabled by a unique multidisciplinary collaboration that includes 20 partners – national laboratories, academic institutions and industry. The collaboration brings together world-leading expertise in all key aspects: from identifying qubits’ quality limitations at the nanometer scale to fabrication and scale-up capabilities into multiqubit quantum computers to the exploration of new applications enabled by quantum computers and sensors.
“The breadth of the SQMS physics, materials science, device fabrication and characterization technology combined with the expertise in large-scale integration capabilities by the SQMS Center is unprecedented for superconducting quantum science and technology,” said SQMS Deputy Director James Sauls of Northwestern University. “As part of the network of National QIS Research centers, SQMS will contribute to U.S. leadership in quantum science for the years to come.”
SQMS researchers are developing long-coherence-time qubits based on Rigetti Computing’s state-of-the-art quantum processors. Image: Rigetti Computing
At the heart of SQMS research will be solving one of the most pressing problems in quantum information science: the length of time that a qubit, the basic element of a quantum computer, can maintain information, also called quantum coherence. Understanding and mitigating sources of decoherence that limit performance of quantum devices is critical to engineering in next-generation quantum computers and sensors.
“Unless we address and overcome the issue of quantum system decoherence, we will not be able to build quantum computers that solve new complex and important problems. The same applies to quantum sensors with the range of sensitivity needed to address long-standing questions in many fields of science,” said SQMS Center Director Anna Grassellino of Fermilab. “Overcoming this crucial limitation would allow us to have a great impact in the life sciences, biology, medicine, and national security, and enable measurements of incomparable precision and sensitivity in basic science.”
The SQMS Center’s ambitious goals in computing and sensing are driven by Fermilab’s achievement of world-leading coherence times in components called superconducting cavities, which were developed for particle accelerators used in Fermilab’s particle physics experiments. Researchers have expanded the use of Fermilab cavities into the quantum regime.
“We have the most coherent – by a factor of more than 200 – 3-D superconducting cavities in the world, which will be turned into quantum processors with unprecedented performance by combining them with Rigetti’s state-of-the-art planar structures,” said Fermilab scientist Alexander Romanenko, SQMS technology thrust leader and Fermilab SRF program manager. “This long coherence would not only enable qubits to be long-lived, but it would also allow them to be all connected to each other, opening qualitatively new opportunities for applications.”
The SQMS Center’s goals in computing and sensing are driven by Fermilab’s achievement of world-leading coherence times in components called superconducting cavities, which were developed for particle accelerators used in Fermilab’s particle physics experiments. Photo: Reidar Hahn, Fermilab
To advance the coherence even further, SQMS collaborators will launch a materials-science investigation of unprecedented scale to gain insights into the fundamental limiting mechanisms of cavities and qubits, working to understand the quantum properties of superconductors and other materials used at the nanoscale and in the microwave regime.
“Now is the time to harness the strengths of the DOE laboratories and partners to identify the underlying mechanisms limiting quantum devices in order to push their performance to the next level for quantum computing and sensing applications,” said SQMS Chief Engineer Matt Kramer, Ames Laboratory.
Northwestern University, Ames Laboratory, Fermilab, Rigetti Computing, the National Institute of Standards and Technology, the Italian National Institute for Nuclear Physics and several universities are partnering to contribute world-class materials science and superconductivity expertise to target sources of decoherence.
SQMS partner Rigetti Computing will provide crucial state-of-the-art qubit fabrication and full stack quantum computing capabilities required for building the SQMS quantum computer.
“By partnering with world-class experts, our work will translate ground-breaking science into scalable superconducting quantum computing systems and commercialize capabilities that will further the energy, economic and national security interests of the United States,” said Rigetti Computing CEO Chad Rigetti.
SQMS will also partner with the NASA Ames Research Center quantum group, led by SQMS Chief Scientist Eleanor Rieffel. Their strengths in quantum algorithms, programming and simulation will be crucial to use the quantum processors developed by the SQMS Center.
“The Italian National Institute for Nuclear Physics has been successfully collaborating with Fermilab for more than 40 years and is excited to be a member of the extraordinary SQMS team,” said INFN President Antonio Zoccoli. “With its strong know-how in detector development, cryogenics and environmental measurements, including the Gran Sasso national laboratories, the largest underground laboratory in the world devoted to fundamental physics, INFN looks forward to exciting joint progress in fundamental physics and in quantum science and technology.”
“Fermilab is excited to host this National Quantum Information Science Research Center and work with this extraordinary network of collaborators,” said Fermilab Director Nigel Lockyer. “This initiative aligns with Fermilab and its mission. It will help us answer important particle physics questions, and, at the same time, we will contribute to advancements in quantum information science with our strengths in particle accelerator technologies, such as superconducting radio-frequency devices and cryogenics.”
“We are thankful and honored to have this unique opportunity to be a national center for advancing quantum science and technology,” Grassellino said. “We have a focused mission: build something revolutionary. This center brings together the right expertise and motivation to accomplish that mission.”
The Superconducting Quantum Materials and Systems Center at Fermilab is supported by the DOE Office of Science.
Fermilab is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.
When a massive star reaches the end of its life, it can explode in a process known as a supernova. The massive star – much more massive than our sun – runs out of fuel in its core. Gravity forces the core to collapse on itself, causing a shockwave to form and spew stellar material into space. Metals, along with heavy elements such as carbon, are expelled into the universe.
Ninety-nine percent of the star’s energy, however, is released in the form of neutrinos, small chargeless particles that barely interact with the matter surrounding them. When some of them arrive on Earth, they arrive in three flavors – electron, muon and tau – in a burst a few tens of seconds long. Along with the fact they rarely interact with matter, each of these neutrinos contains only a relatively small amount of energy, which makes them even harder to observe on Earth.
Scientists have observed supernova neutrinos one time, in 1987. About two dozen neutrinos interacted in several particle detectors located across the globe, and those neutrinos gave us insight into the life cycle of massive stars and how they die. However, two dozen neutrinos aren’t enough to tell us everything about how supernovae occur. Dozens of different theories and models exist to describe the supernova explosion process. To fully describe it, we need to observe more neutrinos from core-collapse supernovae.
DUNE scientists will study streams of neutrinos emitted by exploding stars. DUNE’s unique strength is its sensitivity to a particular type of neutrino called the electron neutrino, which will provide scientists with supernova data not available from any other experiment. Image: Fermilab
Enter the international Deep Underground Neutrino Experiment, hosted by Fermilab. DUNE will study neutrino properties and look for new physics, along with waiting for supernova neutrinos to arrive. The experiment will comprise two particle detectors – a “near detector” at Fermilab and a “far detector” located 1,300 kilometers away at the Sanford Underground Research Facility in South Dakota. The far detector is where most of the supernova neutrinos would be detected. The detector’s massive size – 70,000 tons of liquid argon – along with its impressive sensitivity means that thousands of neutrinos could be observed during the next supernova in our galaxy.
The DUNE collaboration has published a paper about DUNE’s capability for performing supernova physics. The paper discusses what kind of activity DUNE scientists expect to see in their detectors during a supernova burst, how DUNE will know once a supernova occurs, and what results DUNE will be able to extract from the supernova neutrinos.
DUNE will be sensitive primarily to the electron flavor component of the neutrinos — a new type to add to our collection of supernova neutrino data, which so far is made up only of 1987’s sample of antielectron neutrinos. This sensitivity to electron neutrinos sets DUNE apart from other experiments; it is the only experiment in the world that will provide a precise measurement of the electron flavor.
When the supernova neutrinos and argon atoms interact, the protons and neutrons making up the argon atom can be elevated to a higher-energy state. The argon atom then de-excites, and a variety of particles can be emitted as a result. These include gamma rays, neutrons and protons, all of which could leave signals in the DUNE detector. The primary signatures DUNE will look for come from electrons emitted in the interaction. Both the short electron tracks and secondary particles (even shorter “blips”) make up the dominant supernova signals in DUNE.
The neutrinos will leave the exploding star as the core collapse is ongoing. DUNE should be able to distinguish between different stages of the supernova burst because of the different interactions and signals it leaves behind. This can help place constraints on the supernova flux – the number of neutrinos leaving the supernova per second – and the explosion mechanism.
Different supernova flux models will produce different numbers of neutrino interactions and signals in the DUNE detector. For one particular flux model, called the pinched-thermal model, several parameters control the neutrino energies and number of interactions expected. The paper describes the development of a method that measures the flux model parameters from the expected DUNE supernova signal. DUNE’s signal can be affected by the detector’s particular characteristics, detector thresholds and input models. Those uncertainties must be taken into account for the most accurate measure of the flux parameters.
The DUNE collaboration will investigate neutrino properties and why stars die for as long as neutrinos arrive at the detector. As physicists continue to refine and improve the DUNE design, they’ll continue to study neutrinos to unlock the mysteries behind a core-collapse supernova burst.
Erin Conley of Duke University is a physicist on the Deep Underground Neutrino Experiment.
Fermilab neutrino research and U.S. research on DUNE is supported by the Department of Energy Office of Science.
Fermilab is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.