Could specialized 1980s technology be the key to better quantum computers?

There’s a lot I love about the 80s, from the new wave of British heavy metal to the profuse purple blushes favored by makeup artists of the era. But among all the hair, noise and glam were some overlooked superstars: superconducting circuits. In 1980, computer giant IBM bet on this technology to build computers that were as efficient as they were revolutionary. In May of that year, a popular science magazine Scientific American he even put a superconducting circuit on its cover.

But the revolution never came. Superconducting computer chips seemed to have gone the way of permanent and fixed pants. Still, one company kept the research alive. I recently visited SEEQC’s headquarters and the company’s quantum chip foundry in upstate New York, which grew out in part from IBM’s sealed superconducting computing program. There, I learned about the company’s hopes that superconducting chips would play a hand in a new technological revolution—this time with quantum computers.

Inside the SEEQC manufacturing facility, I am surrounded by large machines and technicians in full-body protective suits. In some of these clean rooms, ultra-thin layers of the superconducting metal niobium are repeatedly and carefully deposited on top of layers of dielectric materials, creating a delicate sandwich structure. In others, lithographic devices use light to write complex circuits into these structures, and every tiny trench and groove becomes important to the quantum processes that make them work. The whole floor hums with noise and everything is heated in a yellow light, which I’m told is less disruptive to the chipping process than other colors. As we speak in the conference room next door, CEO of SEEQC John Levy he hands me a version of the company’s superconducting chip, and I’m struck by how modestly small and square it is for a device that aims to change an already futuristic industry.

A problem we need to solve

Superconductors transmit electricity with perfect efficiency, making them significantly different from all the materials we normally use for electronics. When you plug in your phone to charge, the cable or charger will often heat up, reducing the power that was intended for your phone. This is happening to such an extent that in 2017 a computer scientist written by Michael Frank“A conventional computer is basically an expensive electric heater that does a small amount of computation as a side effect.”

A computer with superconducting components would not have this problem. But there’s a catch: all known superconductors must be either extremely cold or subjected to extreme pressure to work. This means that a superconducting computer would only need to be kept a few degrees above absolute zero at all times. Historically, this has proven to be too costly and inconvenient. IBM ended its superconducting computer research efforts in 1983. Conventional heat-spewing computers won out, and somewhat ironically, energy costs only increased and are skyrocketing today, largely due to the rise of artificial intelligence.

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

Quantum computing has come a long way since then, and superconducting qubits have played a role in that progress. Google and IBM use them to power 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 superiority” over classical computers are indisputable, but they highlight the promise that these machines are fundamentally different from any previously built computers.

At the same time, quantum computers have yet to live up to their disruptive promises: they haven’t broken widely used encryption, discovered new miracle drugs, or revolutionized industrial chemistry, to name a few. The path to doing any of these things remains riddled with technical challenges and technical obstacles.

Could part of the answer lie as far back as the 1980s? Levy certainly thinks so. He says his team is building digital superconducting chips that could allow quantum computers to become larger, more powerful and more fault-tolerant all at once. Down the hall from us, researchers are testing the chips in all sorts of tube refrigerators, because he tells me that their goal is not just to make one tool or another 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 filled with superconducting qubits and a refrigerator where that chip must be kept in order to function. Looking from the outside, you can see one neat rectangular box, usually as tall as a person. But there is more to it. Qubits must be controlled and monitored, information must be fed into them from a conventional computer, and the results of their calculations must also be read by one. Qubits are also fragile and error-prone, so they must run error-correction algorithms that require sophisticated controllers that monitor and adjust many qubits at once in real time. So the non-quantum components of a quantum computer are remarkably important to its operation—and they take up a lot of space and use a lot of energy. Behind every tall refrigerator that houses qubits are usually several other equally tall cabinets filled with racks of conventional energy-wasting equipment. And there are countless cables connecting the quantum and non-quantum parts of the computer.

Adding more qubits, which you have to do to make the computer more powerful, requires even more cables. “You can’t physically keep adding cables,” he says Shu-Jen HanChief Technical Officer of SEEQC. Not only the space inside the refrigerator becomes a problem, but each cable brings some heat with it, which then interferes with the qubits and destroys their performance. How qubits are connected, controlled, wired, and packaged may seem like a silly side of technology that only engineers and experts should care about, but it has become one of the issues holding back quantum computers from further maturing.

The SEEQC chip I was holding could solve a lot.

It looks like you might imagine a computer chip – small and flat, with a slightly larger metal rectangle on top. Levy explains that the small rectangle contains superconducting qubits, while the larger one is a conventional computing chip made of superconducting materials that can digitally control these qubits. Because they are both superconducting, 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 putting any extra heat into the fridge is one clear advantage, but the superconducting control chip is also much less power-hungry. SEEQC predicts it could achieve a billion-dollar improvement in the energy efficiency of a quantum computer. Estimates from the Quantum Energy Initiative suggest that some designs for large, fault-tolerant quantum computers would require more power than existing conventional supercomputers—those room-filling behemoths—and much of that power consumption can be attributed to classical computing components.

Because the two chips—the quantum one that computes and the classical one that controls it—can be close together, there is less delay in transmitting instructions to the qubits and in how their calculations are loaded and corrected for errors. Levy also told me that because the chip’s signals are digital, the qubits they control 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 still adhere to. He told me that when he envisions a useful and powerful quantum computer, it’s a device with a million qubits that can contain entire rooms full of machines, more like a particle accelerator than a laptop or rack in a data center. The SEEQC team is working to avoid this oversized future. For computer fans, I think Mac not ENIAC.

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

There are also physical problems – superconductors tend to fill up with tiny quantum vortices when a magnetic field like the one used to tune some qubits is nearby. Oleg Muchanovsenior scientist at SEEQC, told me about a method the firm has innovated to deal with this problem, where the eddies are swept away by a different electromagnetic field. Long story short, I flashed back to graduate school and sat in a superconductor physics class—even the most futuristic technologies cannot escape the vagaries of fundamental quantum effects.

Could the superconducting circuits pick up and send me even further? Maybe it’s the right time for the 80s to return to the quantum world, although I hope we leave the shoulder pads behind.

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