Superconductor experts at Fermilab lead efforts to build revolutionary quantum computers

Eric Holland working in the Quantum Lab at Fermilab’s Industrial Center Building (ICB).
Scientists at the U.S. Department of Energy’s Fermilab are building a quantum computer based on superconducting technology. They’re working in partnership with Rigetti Computing, Northwestern University, Ames Laboratory, NASA, and INFN, among others. (Reidar Hahn/FERMILAB)

By Shivani Majmudar and Grace Rodgers 
Medill Reports

The Fermilab National Accelerator Laboratory, just west of Chicago, is leading one of five national centers to advance quantum computing — a move to speed up computational science and technology while harnessing vast new levels of information.

Taking a multidisciplinary approach, working in collaboration with 19 scientific, academic and industrial partners, Fermilab is posed to make revolutionary breakthroughs in quantum science far beyond what is currently possible. Its new Superconducting Quantum Materials and Systems Center was selected in August to receive $115 million federal dollars over the next five years.

They’re working to build the world’s most advanced quantum computer — a machine that promises unparalleled computing power to deliver solutions to complex problems within seconds instead of years, according to SQMS Deputy Director James Sauls, Ph.D., a physicist with Northwestern University.

“The implication of solving very hard problems such as factoring very large numbers would really have an enormous impact on the finance industry and national security apparatus,” Sauls said.

Quantum computers differ from traditional computer systems at an elementary level. The basic unit for computing and information processing in traditional computers is called a “bit”, which can exist as one of two distinctstates: zero and one. Quantum computers are instead based on quantum bits, or “qubits”. Qubits can be at either voltage state — or a combination of the two. Processing at this “superposition” state is what would give quantum computing its technological edge because its qubits can complete exponentially more operations as traditional bits.

“If we had two qubits coupled together, we could perform four numerical operations on those bits, whereas it would just be two for that of two classical bits. If we had three qubits, we could perform eight parallel computations. Four, 16, and so forth,” Sauls explained.

Yuxin Zhou working on scientific processes at the Lamont-Doherty Earth Observatory laboratory.
One aspect of quantum technology that makes building a quantum computer really challenging is how small the atoms are, Sauls said. Typically, atoms are about one nanometer, which is less than one billionth of a meter. For scale, this is one superconducting qubit next to a United States penny. (Reidar Hahn/FERMILAB)

Beyond its mathematical potential, which alone could have transformative impacts in multiple industries from cybersecurity to pharmaceutical research, quantum technology is also being used to advance material science and our understanding of fundamental particles in the universe.

Sam Posen, Ph.D., a scientist at Fermilab, is hoping to apply quantum science to detect huge clouds of physical matter in the atmosphere that modern technology can’t see — something proposed to bedark matter.

“We can take this wonderful technology that is being developed to look at these very sensitive low energy systems, quantum computing systems, and apply it to the problem of searching for new particles predicted by theorists,” Posen said. “It’s very synergistic.”

For a breakdown on the science of dark matter, watch the video below.

The SQMS Center’s primary research goal is to lengthen the duration a qubit exists in the engineered combination state like the superposition. This is one of today’s most pressing questions in quantum information science because of its direct relationship to greater computing power and processing speed. Scientists call this the qubit’s coherence.

The current state of the art technology gives qubits a coherence of 38 microseconds. A microsecond is one millionth of a second. It becomes difficult for atoms to hold the superposition state any longer than this because they’re embedded in a busy environment with factors such as radiation and thermal energy.

“The presence of thermal noise can actually kind of tickle the atom in its high energy state and force it to make a transition [to its low energy state]. Then you lose the superposition property,” Sauls explained.

But the team at the SQMS Center has proposed to increase qubit coherence by an additional factor of ten in just three years.

To achieve this ambitious goal, they are turning to existing, groundbreaking particle accelerator technology called superconducting resonators. Fermilab actually revolutionized this technology which can assist in the search of hypothetical, subatomic building blocks of matter.

Fermilab has already fabricated the highest coherence times for superconducting resonators. Now, they are hoping to apply this theory and machinery to advance quantum computing. If they reach this milestone, scientists would be on track to spearhead a full quantum computer of extraordinary power — with 100 qubits — within five years.

While the tasks ahead may seem daunting, Sauls is appreciative of the advancements in quantum technology in recent years. Sauls largely credits new cryogenic technology, which drastically lowers temperatures to reduce thermal noise surrounding qubits, with transforming the entire quantum device industry in the past decade.

Looking ahead, the realm of possibilities for quantum technology is exciting, Posen said, even if the next few years mainly involve trial and error.

“There’s the potential for new things that we haven’t thought of, directly using these [technologies] for new discoveries.”

Shivani Majmudar and Grace Rodgers are health, environment and science reporters at Medill. You can follow them on Twitter at @spmajmudarr and @gracelizrodgers.