The next great scientific and technological revolution: quantum information science

University of Illinois at Urbana-Champaign poised to play leading role in national QIS research and development efforts

Siv Schwink
for Illinois Physics

Researchers collaborating across physics, engineering, and computer science have shown that quantum mechanics—one of the most successful theories of physics that explains nature at all scales, from electrons, to atoms, to neutron stars, to the big bang—can be a powerful platform for information processing, data storage, and secure communications. Quantum information science (QIS) has emerged as a rapidly growing and exciting multidisciplinary field having implications for a broad range of astounding advancements to today’s technologies. A recent surge in global QIS research efforts is signaling the next great scientific and technological revolution. 

Scientists and engineers at research institutions and in the tech-industry are putting large stakes on what’s to come. In 2016, China launched the Micius “quantum satellite” and by 2018 had successfully run quantum communications experiments in space—an important first step toward the eventual creation of a global quantum communications network. In 2018, Israel allocated $80 million for the development of quantum computing technology, and in the U.S., every major research funding agency launched special programs to support QIS. By the end of the year, the U.S. National Quantum Initiative Act had passed both the House and the Senate and was signed into law by President Donald Trump on December 21, 2018. This legislation, intended to secure the U.S.’s leadership in QIS, commits $1.2 billion in funding over a five-year period toward the development of QIS technologies and the training of a QIS-smart workforce. 

It will likely be some years before the first quantum processors capable of performing large-scale computations are brought online. Many fundamental questions remain on how to optimally incorporate the marvelous, completely unintuitive properties of quantum mechanics in proposed new technologies. But it’s evident that a quantum revolution is coming, bringing progress we can’t even imagine. After all, before the first laser was invented in the 1960s, who could have dreamed of today’s ubiquitous applications of amplified light? Lasers are used in grocery-store scanners, CD and DVD players, laser printers, surgical tools, medical and scientific spectroscopy, firearm and munitions targeting, traffic enforcement, internet fiberoptics, and more. It’s fair to say that quantum technologies likewise hold great surprises in store.

New multi-disciplinary center to accelerate QIS research

With faculty members in several departments already doing QIS-related research, the University of Illinois at Urbana-Champaign is in a good position to help lead the coming revolution. On October 29, 2018, the U of I announced that it would invest $15 million to establish a new research center that would draw on and expand Illinois’ expertise in QIS. The Illinois Quantum Information Science and Technology Center (IQUIST) will bring together quantum-science experts across multiple Illinois Engineering departments and other units on campus.

IQUIST’s newly named director, Physics Professor Paul Kwiat, is a pioneer in QIS research, especially noted for his groundbreaking quantum-communication experiments using entangled and hyperentangled photons. Kwiat says the new center is exactly what’s needed to accelerate progress in the development of QIS technologies and QIS education at the U of I.

“To make quick progress, we need a broad spectrum of scientists and engineers to converge and learn one another’s languages so that we may effectively work together across our different research paradigms,” says Kwiat. “We need computer scientists, materials engineers, electrical engineers, and others with a strong interest in developing technologies using the unique, powerful capabilities of quantum mechanics. Each discipline has its own way of tackling problems, its own methods and tools, and its own strengths. IQUIST will enable QIS researchers at Illinois to collaborate across disciplines to better exploit those strengths, to explore promising new ideas more rigorously, and to benefit more immediately from one another’s work.”

Physics Professors Dale Van Harlingen and Brian DeMarco have been appointed IQUIST’s new executive associate director and associate director for educational programs, respectively. Van Harlingen brings expertise in superconductivity and its potential applications in quantum technologies, and DeMarco brings expertise in trapped ion experiments, which they will apply toward the development of IQUIST’s planned quantum processor testbed.

DeMarco asserts, “Illinois is positioned to have a strong impact on QIS research, including algorithm development, creating key technologies such as quantum repeaters and communication channels, and research into the materials needed for next-generation qubits [quantum bits].”

The center will also develop a focused program to educate the next-generation quantum workforce. DeMarco, who also serves as Illinois Physics’ associate head for undergraduate programs, comments, “Illinois Physics is one of the largest and top-ranked physics departments in the U.S., and we are working to solve the quantum workforce challenge by developing new undergraduate and master’s degree programs in QIS.”

In the U of I press release, Chancellor Robert Jones commented, “Our campus has a legacy of groundbreaking contributions to fundamental science and the development of technologies that have shaped society over the past century, including the first automatic computer, magnetic resonance imaging, light-emitting diodes, and the first modern internet browser—not to mention the first computer built and owned by an educational institution. Today, we are pleased to announce near-term concrete actions that will advance this critical area of national need and importance.”

The three key organizers wasted no time in making the center a reality. By the end of the calendar year, they had acquired administrative offices in the Frederick Seitz Materials Research Laboratory and research space in the basement of the Engineering Sciences Building for the development of the quantum processor testbed. The testbed is expected to involve trapped ion qubits, conventional and topological superconducting qubits, and possibly semiconductor-defect-state qubits, with photonic interconnects coupling them. IQUIST will acquire state-of-the-art equipment for the fabrication of quantum materials and devices, including an electron-beam writer, thin-film growth and processing equipment, a dry dilution refrigerator, and microwave electronics.

The three key IQUIST organizers have also already outlined the new center’s administrative structure and governance; assembled its inaugural membership of 24 U of I scholars from the Departments of Physics (17), Electrical and Computer Engineering (3), Computer Science (2), Mechanical Engineering (1) and Mathematics (1); formed the IQUIST Scientific Advisory Committee comprising eight of its members; and invited thirteen U of I researchers from College of Engineering units to join IQUIST as affiliates, including six from Illinois Physics.

An IQUIST retreat for members and affiliates will take place on Martin Luther King Jr. Day, on January 21, 2018, at the I-Hotel and Conference Center in Champaign. The agenda includes opportunities to discuss future plans for the center, as well as research and funding opportunities.

In conjunction with the new center, the university has authorized at least eight QIS faculty lines. Searches to fill these positions are already underway within the Departments of Physics, Electrical and Computer Engineering, and Computer Science. 

Van Harlingen notes, “We expect the number of members and affiliates to grow significantly as we hire new faculty and as more faculty start projects and obtain funding in QIS. We also expect the immediate hiring of postdocs and/or technical staff for designing and engineering the testbed and for advanced thin-film and device fabrication. We will also soon hire a managing director, to handle the day-to-day administrative operations of the center.”

Plans are also underway to establish an internal IQUIST Executive Advisory Committee composed of department heads and laboratory directors in the College of Engineering, in addition to an IQUIST External Advisory Board composed of academic, national lab, and industrial leaders in QIS. Part of IQUIST’s mission will be to foster and expand collaborations with industry, national labs, and other academic institutions, such as the University of Chicago, Argonne National Laboratory and Fermilab. As a participant in the Discovery Partners Institute’s Illinois Innovation Network, IQUIST will contribute to strengthening Illinois’ economy through high-tech workforce and next-generation technology development.

New QIS partnerships

On October 30, 2018, the University of Illinois at Urbana-Champaign announced it had joined the Chicago Quantum Exchange (CQE) as its final core member, making it one of the largest QIS collaborations in the world. The CQE was formed last year as an alliance between the University of Chicago and the two Illinois-based national laboratories, Argonne and Fermilab. Van Harlingen serves as the U of I representative on the CQE steering committee, which has one member from each of the four core-member institutions.

Van Harlingen comments, “The CQE is a collaboration designed to bring academic, national lab, and industrial institutions together to take advantage of Chicago’s visibility and opportunities in QIS. CQE will focus first on attracting funding through the National Quantum Initiative—that planning has already started. There will also be collaborative projects, educational programs, and industrial partnerships and internships. Eventually, we expect to have research laboratories, office space, and faculty, postdocs, and students located in Chicago.”

According to the U of I’s October 30 press release, the initiative is a major step in an expanded series of collaborations between UChicago and the Urbana campus, deepening their connections in the Discovery Partners Institute and the Illinois Innovation Network.

The CQE already has multiple projects underway, including plans to develop one of the world’s longest quantum communication links to test technology that one day could be the basis for an unhackable network and distributed quantum sensors. It will stretch 30 miles between Argonne in Lemont and Fermilab in Batavia, with a new link to connect to U of I’s Urbana campus.

Illinois Physics represented at QIS summits and congressional briefings

Two Illinois Physics faculty members were invited to attend the Advancing American Leadership in QIS Summit, held at the White House in Washington, D.C., on September 24, 2018. DeMarco was joined by the University of Illinois System Vice President for Economic Development and Innovation, Founder Professor of Physics Ed Seidel. Seidel is the former director of the National Center for Supercomputing Applications in Urbana. Prior to that, he served as co-chair of the National Science and Technology Council’s Subcommittee on Quantum Information Science while he led the Directorate for Mathematical and Physical Sciences at the National Science Foundation. Top scientists and U.S. officials at the summit coordinated a long-term competitive approach to QIS research and infrastructure development across America, with strong collaboration among private and public efforts.

Illinois Physics was also represented at the inaugural two-day Chicago Quantum Summit, which took place November 8-9, 2018, and was hosted by the CQE. Representing the U of I at the summit were DeMarco, Kwiat, and Van Harlingen. Van Harlingen served as a panelist.

This summit brought together leading experts in quantum information science, representatives of pertinent government agencies, and tech-industry leaders to advance U.S. efforts in QIS—and to position Illinois at the forefront of that race.

DeMarco returned to D.C. for two congressional briefings in January, as part of an Illinois delegation that included representation from UChicago, Northwestern, Fermilab, and Argonne.

“We met with House and Senate staffers in two separate one-hour meetings to educate their respective congressional members about QIS—what’s exciting, where opportunities lie, and what strengths the State of Illinois brings—so they can appreciate and advocate for our QIS programs,” states DeMarco.

Separating the hype from the vital scientific and technological endeavor

Media attention on esoteric QIS research and its implications for future technologies will inevitably result in some misinterpretations. So what will we use quantum computers for?

DeMarco explains, “The future of many activities central to human life, including transportation, medicine, and manufacturing, will be transformed by improvements in computing, networking, and sensing over the next century. However, computers, networks, and devices based on conventional technology are inherently limited in their ability to tackle some of the most important problems we will face.

“Quantum computers and networks would leverage the physics of quantum mechanics to tackle these problems at a magnitude much larger than any future supercomputer. For example, a large-scale quantum computer could determine the properties of chemical bonds key to new pharmaceuticals for complexes larger than any supercomputer could ever deal with. Beyond medicine, this may also be a route to optimizing artificial photosynthesis for carbon management, which may be central to preventing disaster from climate change.”

But will quantum computers someday completely replace classical computers? According to Kwiat, that’s unlikely given the laws of quantum mechanics.

Kwiat explains, “Most of what most people do on classical computers—watching cat videos, doing a calculation of something, or writing an email to someone and cc’ing someone else—involves copying information. You can copy classical information, but you can’t copy quantum information—that’s what makes quantum cryptography secure. 

“A classical computer is also more robust against certain encoding errors, and it would be very expensive to achieve the same in a quantum computer. Because of the way a classical computer can do error correction, the parts don’t need to be that good. Any bit that’s close to a 1 is called a 1, and any bit that’s close to a 0 is called a 0. Therefore, if there’s a little bit of fluctuation in the data, it’s self-correcting. But in quantum computing, all of those fluctuations are totally different quantum states, so those little fluctuations would become big errors. A qubit is non-binary—it can host near limitless states, which is what makes it so powerful.”

What will quantum computers do better than classical computers? Researchers have already demonstrated that they can use quantum emulators to solve quantum mechanics problems and to simulate molecular problems. At Illinois Physics, a growing team of atomic, molecular, and optical physicists is doing just that.

Kwiat notes, “Quantum mechanics problems include things like figuring out how proteins could fold up or how medicines might work, or how you could design a better biodegradable chemical fertilizer for maximum crop yields. These kinds of results would have huge impact all over the world. Quantum computers would also be better at optimization problems than classical computers—they could make myriad processes instantly and responsively faster and more efficient, including internet services.

“On the other hand, a case where quantum computing would not serve as well as classical computing, at least for now, is in modeling and forecasting weather, which requires more bits than we currently have the ability to produce in terms of qubits. For now, a quantum computer is good when there is one right answer.”

That said, Kwiat says it’s impossible to predict all of the possible future applications of quantum technologies, and we should expect the unexpected.

“Take for example the idea of a quantum network, which would have several potential applications, not only for encrypted communications,” Kwiat notes, “It’s been proposed that we could someday use a quantum network as a telescope, with each node acting as an eye on the sky. The combined effect would be a telescope equivalent to the size of the Earth. With that kind of resolution and magnification, we could see things in deep space far surpassing what we ever believed possible before.”

DeMarco and Kwiat are each involved in separate NASA missions that bring QIS research to space. DeMarco chairs the NASA Fundamental Physical Sciences review board, which has oversight responsibility for the recently launched Cold Atom Laboratory (CAL). CAL scientists are currently conducting ultracold atom experiments in microgravity conditions on the International Space Station to learn more about the fundamental properties and interactions of matter at near-absolute zero temperature.

Kwiat is the lead investigator on a NASA mission involving researchers from MIT Lincoln Laboratories, the Jet Propulsion Laboratory, and Oak Ridge National Laboratory, to develop advanced space-based quantum communication capabilities. The initial goal is to transmit entangled and hyperentangled photons between the International Space Station and Earth, which could enable unhackable communication and eventual long-distance quantum networks.