Alex Müller
The IBM researcher shared a Nobel Prize in Physics in the 1980s. It was just the beginning of his legacy.
Alex Muller in a lab with components on the table behind him

Karl Alex Müller figures prominently in the history of IBM. A physicist from Switzerland, Müller conducted research on superconductivity with fellow IBM researcher Georg Bednorz. Their discovery earned the duo the Nobel Prize for Physics in 1987 and has proven seminal in advancing applications by which select materials can radically improve both the power and efficiency of electrical transmission.

Imagine the difference between sliding a hockey puck across a bumpy old linoleum floor versus across a sheet of ice. As a conveyance mechanism, or conductor, the linoleum is relatively inefficient. It saps energy from the puck and impedes its travel. The ice, on the other hand, offers far less friction, enabling the puck to travel faster and farther. Now, instead of a puck, think of a series of electrons flowing in an electrical current. When Müller and Bednorz began their research, the world only had the equivalent of linoleum floors — copper or aluminum wire, for instance. These were slippery, but not frictionless, causing a voltage drop from one end of a wire to the other. So, the duo set out to discover the ideal superconductor, which would offer zero resistance under proper conditions, enabling electricity to flow without dissipating power or exhausting heat.

Their discoveries fundamentally advanced basic science and set the stage for the development of many current and future commercial applications, including magnetic resonance imaging (MRI), high-speed rail, high-efficiency wind turbines and smart-grid power transmission.

A dual career in academia and at IBM

Müller was born in Basel, Switzerland, in 1927 and moved with his family to Austria, where his father studied music. He subsequently repatriated with his mother to Switzerland and eventually relocated to his grandparents’ house in Lugano, Italy, where he became fluent in Italian. His mother died when he was 11, and — as he told an interviewer from the Max Planck Institute in 2015 — “responsibility for me and my future life passed to my father.”

Under his father’s guidance, Müller later enrolled in the Evangelical College in Schiers, Switzerland, and earned his doctorate in physics from the Swiss Federal Institute of Technology. He married and had two children. “My wife and the children with their families played and still play an essential role in my life,” he said. “They accompanied me during all periods of my career and are an anchor for my philosophy of life and science.”

In 1958, he joined the Battelle Institute in Geneva as manager of the magnetic resonance group and soon became a lecturer at the University of Zurich. Simultaneously, he worked at the IBM Research laboratory in Zurich, where he remained until his retirement. Müller became a full professor in 1970 and two years later became manager of the IBM lab’s physics department. He wrote more than 200 technical publications while holding membership in the Executive Committee of the Groupement Ampère and the Ferroelectricity Group of the European Physical Society, along with many other prestigious associations.

In 1982, Müller was named an IBM Fellow, the company’s highest technical recognition, and set about deepening his specialty in oxide ceramics, a class of inorganic metallic compounds. Knowing that supercooling was expensive with established materials, he began searching for substances that would become superconductive at temperatures higher than those in use at that time. In 1983, he made the pivotal decision to recruit Georg Bednorz, who had joined IBM Research the previous year, to help systematically test various oxides.

A scientific breakthrough

In 1911, Dutch scientist Heike Kamerlingh Onnes discovered a process thought to be the closest approximation to a perpetual motion machine found in nature. He found that superconductivity, or zero electrical resistance, could be achieved using certain alloys and chemical compounds that lost all of their electrical resistance when cooled close to absolute zero — in his case, 4.19 Kelvin (K) for liquid mercury. (Absolute zero is 0 Kelvin, -273 degrees Celsius, or -459 degrees Fahrenheit.) In subsequent decades, superconductivity was found in lead at 7 K, in niobium at 10 K, and in niobium nitride at 16 K.

For the next three-quarters of a century, progress on finding compounds that conducted at higher, more practical temperatures, was excruciatingly slow. New materials discoveries typically only improved conductive temperatures by a fraction of a degree. And then, circa 1973, even incremental progress seemed to stall out, having peaked at 23 K with another niobium-based material. Superconductivity was seen by many as a theory with little hope of practical applications.

Then, in 1983, Bednorz and Müller noticed that perovskites, a class of oxides, offered the promise of conducting electricity at more achievable temperatures. To obtain a chemically stable material, the duo added barium to crystals of lanthanum-copper-oxide to produce a ceramic that eventually became the first successful high-temperature superconductor. The revelation was initially greeted with skepticism because ceramics were generally considered insulators, not conductors, but the new material withstood repeated testing to demonstrate superconductivity at 35 K.

The simplest and most practical significance was that 35 K requires less cooling with liquid helium (4.2 K), which is a very limited resource. Superconductors with transition temperatures above 77 K can be cooled with liquid nitrogen, which can be relatively easily condensed out of air by refrigeration techniques. This makes the cooling process easier and less expensive. The other practical aspect of the higher temperature discovery was that it revealed a different model for superconductivity, which opened a whole field of research into whether room-temperature superconductivity might someday be attainable.

A quick path to the Nobel Prize

In January 1986, Müller and Bednorz unveiled their discovery and spawned a flurry of activity among physicists who imagined exciting new applications in electrotechnology and microelectronics. Within a year, several groups had prepared their own versions of the IBM-made compound and reported similar results. By March 1987, thousands of scientists and engineers were researching other versions of the new class of oxide superconductors in hopes of unlocking more applications.

Scientists soon developed materials that achieved superconductivity at 77 K — the key threshold for using liquid nitrogen. “This discovery is quite recent, less than two years old,” said Gösta Ekspong of the Royal Swedish Academy of Sciences in late 1987, “but it has already stimulated research and development throughout the world to an unprecedented extent.”

The fevered activity peaked at the March 1987 American Physical Society meeting in New York. Dubbed the “Woodstock of Physics,” the event counted more than 50 scientists presenting discoveries that achieved dramatically higher superconductivity temperatures than ever before.

Müller and Bednorz were honored for their work later that year with the Nobel Prize — the shortest time ever recorded between a discovery and the award for any scientific Nobel.

Alex Müller died at age 95 in 2023.

Müller and Bednorz were honored for their work with the Nobel Prize
From MRIs to mag-lev trains
Superconductivity today and tomorrow

The quest to fully harness the potential of high-temperature superconductors (HTS) continues, with a focus primarily on electric power transmission, high-speed rail, and other novel modes of frictionless transportation. “There are lots of ways to make something hover,” explained IBM Research scientist Kevin Roche. “If you cool down a material to the point where it actually becomes superconducting, it will become a magnetic mirror.”

Nations around the world are testing energy-efficient power cables using high-temperature superconductors. Nearly every hospital now employs magnetic resonance imaging scanners (commonly known as MRIs) using small superconducting coils to produce a rotating magnetic field that creates detailed images of the human body. Some countries are even testing trains that use onboard magnets to levitate vehicles above steel rails, potentially making trains much faster and more efficient.

However long it takes for science and industry to discover the full benefits of high-temperature superconductivity, Müller’s place in the pantheon of IBM luminaries — alongside his battery mate Bednorz — will endure.  

If you cool down a material to the point where it actually becomes superconducting, it will become a magnetic mirror Kevin Roche IBM Research scientist
Related stories Georg Bednorz

The pioneering researcher shared the Nobel Prize for his work in superconductivity

High-temperature superconductivity

IBM’s Nobel Prize-winning work on energy efficiency promises to unlock great innovations across industry and society