Could a niche 80s technology be the key to better quantum computers?

There are many things I love about the 1980s, from the new wave of British heavy metal to the heavy purple blush favored by makeup artists of the era. But among all the hair, noise and glamour, there were a few overlooked superstars: superconducting circuits. In 1980, computer giant IBM relied on this technology to build computers so efficient that they would be revolutionary. In May of the same year, the popular science magazine Scientific American even put a superconducting circuit on its lid.

But the revolution never happened. Superconducting computer chips seemed to have gone the way of perms and ankle-length pants. Yet one company has kept the research alive. I recently visited SEEQC’s headquarters and the company’s quantum chip foundry in upstate New York, which grew in part from IBM’s closed superconducting computer program. There I learned about the company’s hopes that superconducting chips would contribute to a new technological revolution – this time with quantum computers.

Inside the SEEQC manufacturing plant, I’m surrounded by large machines and technicians in full protective suits. In some of these clean rooms, ultrathin layers of superconducting metallic niobium are repeatedly and carefully deposited onto layers of dielectric materials, creating a delicate sandwich-like structure. In others, lithography devices use light to write complex circuits onto these structures, and each little trench and furrow becomes important to the quantum processes that make them work. The whole floor hums with noise and everything is bathed in a yellow light which, I am told, interferes less with the chip-making process than other colors. As we chat in an adjacent conference room, SEEQC CEO John Levy hands me a version of the company’s superconducting chip, and I’m struck by how modest and boxy it is for a device that aims to change an already futuristic industry.

The problem we need to solve

Superconductors transmit electricity with perfect efficiency, which makes them distinctly different from all the materials we commonly use for electronics. When you plug your phone in to charge, the cord or charger often heats up, decreasing the power going to your phone. This is happening so much that in 2017, computer scientist Michael Frank wrote: “A conventional computer is essentially an expensive electric heater that performs a small amount of calculations as a side effect. »

A computer with superconducting components would not have this problem. But there’s a catch: All known superconductors must either be kept extremely cold or be subjected to extreme pressure to work. This means that a superconducting computer would always have to be kept just a few degrees above absolute zero. Historically, this has proven to be too expensive and impractical. IBM ended its research efforts into superconducting computing in 1983. Conventional heat-producing computers won out and, ironically, the energy cost of computing only increased, climbing today largely because of the AI ​​boom.

But superconductors found themselves back in the spotlight a few decades later. In 1999, a team of Japanese researchers made the first superconducting quantum bit, or qubit, which is the building block of a quantum computer. This was a fundamentally different proposition from what the researchers had attempted a decade earlier. Instead of replicating commonly used computing with superconducting materials, they opened the door to an entirely new type of computing, with devices that process information through mechanisms that simply don’t exist in a conventional computer.

Since then, quantum computing has come a long way, and superconducting qubits have played a role in this progress. Google and IBM use them to drive some of today’s most powerful quantum computers, and these devices have begun to solve scientifically interesting problems with encouraging success. Some demonstrations showing “quantum supremacy” over classical computers are uncontested, reinforcing the promise that these machines are fundamentally different from any computers built before.

At the same time, quantum computers have yet to deliver on their disruptive promises: They haven’t broken widely used encryption, discovered new wonder drugs, or revolutionized industrial chemistry, to name a few. The path to achieving any of these things remains fraught with technical pitfalls and engineering obstacles.

Does part of the answer lie in the 1980s? Levy certainly thinks so. He says his team is building digital superconducting chips that could allow quantum computers to become simultaneously larger, more powerful and more easily error-proofed. Down the hall, researchers are testing chips in all sorts of tubular refrigerators, as he tells me they aim not just to make an additional tool or component, but to replace many of the components that currently make quantum computers bulky and inefficient.

At its core, a superconducting quantum computer consists of a chip full of superconducting qubits and a refrigerator in which that chip must be kept to function. Looking from the outside, you can see a sleek rectangular box, usually as tall as a person. But there is more. The qubits must be controlled and monitored, information must be entered into them from a conventional computer, and the results of their calculations must also be read by it. Qubits are also fragile and prone to errors. They must therefore run error-correcting algorithms, which require sophisticated controls that monitor and adjust multiple qubits at once in real time. So the non-quantum components of a quantum computer are extremely important to its operation – and they take up a lot of space and consume a lot of power. Behind each tall refrigerator housing qubits, there are usually several other equally tall cabinets filled with racks of energy-wasting conventional devices. And there are myriad cables connecting the quantum and non-quantum parts of the computer.

Adding additional qubits, essential to making a computer more powerful, requires even more cables. “Physically, you can’t keep adding cables forever,” says Shu-Jen Han, technical director of SEEQC. Not only does space in the fridge become a problem, but each cable brings heat, which disrupts the qubits and ruins their performance. How qubits are connected, controlled, wired, and packaged may seem like a core facet of the technology that only engineers and experts should worry about, but it has become one of the problems holding quantum computers from further advancement.

The SEEQC chip I had could solve a lot of this problem.

It looks like what you imagine a computer chip to be: small and flat, with a metal rectangle on top of a slightly larger one. Levy explains that the small rectangle contains the superconducting qubits, while the larger one is a conventional computer chip made from superconducting materials that can digitally control these qubits. Because they are both superconductors, they can be placed in the same refrigerator, eliminating the need for many of the room-temperature devices that quantum computers currently rely on.

Not introducing additional heat into the refrigerator is an obvious advantage, but the superconducting control chip is also much less power hungry. SEEQC predicts that it could improve the energy efficiency of a quantum computer by a billion times. Estimates from the Quantum Energy Initiative indicate that some designs of large error-proof quantum computers would require more power than existing conventional supercomputers – those behemoths that fill entire rooms – and that much of that energy consumption can be blamed on classical computer components.

Because the two chips – the quantum one that calculates and the classical one that controls it – can be close together, there are fewer delays in transmitting instructions to the qubits and in how their calculations are both read and corrected for errors. Levy also told me that because the chip’s signals are digital, the qubits it controls should also have less “crosstalk,” or unintended interactions that make them more error-prone.

In 2025, I spoke with David DiVincenzo, who nearly 20 years ago proposed seven conditions for building a working quantum computer that researchers are still following. He told me that when he imagined a useful and powerful quantum computer, it was a million-qubit device that could include entire rooms full of machines, looking more like particle collider facilities than a laptop or a rack in a data center. The SEEQC team is working to avoid this oversized future. For computer fans, think Mac and not ENIAC.

The SEEQC team is currently testing its chips in various configurations and with qubits made both by its own researchers and those of other quantum computer makers. Levy says early testing shows good performance across the board, a testament to the chip’s versatility. At the same time, all tests have been limited to a small number of qubits, generally less than 10, which is several orders of magnitude smaller than the practical quantum computers of the future that the company hopes to implement.

Physics problems also arise: superconductors tend to fill with tiny quantum vortices when there is a magnetic field nearby, like those used to tune some qubits. Oleg Mukhanov, scientific director of SEEQC, told me about the company’s innovated method to solve this problem, where the vortices are swept by another electromagnetic field. In short, I was transported back to my graduate school days in superconductor physics classes: even the most futuristic technologies cannot escape the vagaries of fundamental quantum effects.

Could superconducting circuits rise and send me even further away? Perhaps it’s time for the ’80s to make their return to the quantum world, although I hope we leave the shoulder pads behind.