MIT Professor Emeritus Keith H. Johnson, a quantum physicist who was a pioneer in employing theoretical methods in materials science and later utilized his knowledge for independent filmmaking, passed away in June in Cambridge, Massachusetts. He was 89 years old.
A faculty member in MIT’s Department of Materials Science and Engineering (DMSE), Johnson applied basic principles to comprehend how electrons operate in materials — that is, he referred to fundamental laws of nature to predict their behavior, instead of depending solely on experimental data. This methodology provided researchers with a more profound understanding of materials prior to their fabrication in a laboratory, assisting in establishing the foundation for contemporary computer-aided methods of material discovery.
DMSE Professor Harry Tuller, who worked alongside Johnson in the early 1980s, points out that while first-principles calculations are currently routine, they were quite rare at that time.
“Solid-state physicists primarily concentrated on modeling the electronic structure of materials like semiconductors and metals using extended wave functions,” Tuller remarks, referencing mathematical models of electron behavior in crystals — a significantly quicker technique. “Keith was among the few who employed a more localized chemical perspective.”
This localized perspective enabled Johnson to more thoroughly investigate materials with minor imperfections known as defects, such as in zinc oxide. His techniques enhanced the comprehension of materials employed in devices like gas sensors and water-splitting systems for hydrogen fuel. It also provided him with greater understanding of intricate systems such as superconductors — materials that conduct electricity without resistance — and molecular materials like “buckyballs.”
Johnson’s inquisitiveness took a creative turn in 2001’s “Breaking Symmetry,” a sci-fi thriller he wrote, produced, and directed. Released on YouTube in 2020, it has garnered over 4 million views.
Pioneering theorist at DMSE
Born in Reading, Pennsylvania, in 1936, Johnson exhibited an early fascination with science. “After receiving a chemistry set as a child, he created a laboratory in his parents’ basement,” shares his wife, Franziska Amacher-Johnson. “His initial experiments were intense — once resulting in an evacuation of the house due to chemical fumes.”
He obtained his undergraduate degree in physics at Princeton University and earned his doctorate from Temple University in 1965. He joined the MIT faculty in 1967, at that time called the Department of Metallurgy and Materials Science, and remained there for nearly three decades.
His early application of theory in materials science paved the way for further innovations. To simulate the behavior of electrons in small groups of atoms — such as material surfaces, interfaces between differing materials, and defects — Johnson employed cluster molecular orbital calculations, a quantum mechanical method focusing on electron behavior in closely packed atomic configurations. These calculations provided insights into how defects and interfaces affect material performance.
“This aligned wonderfully with our goals in comprehending the roles of bulk defects, interface and surface energy states at grain boundaries and surfaces in metal oxides in affecting their efficiency in various devices,” Tuller explains.
In one initiative, Johnson and Tuller co-supervised a PhD student who conducted both experimental evaluations of zinc oxide devices and theoretical modeling using Johnson’s methodologies. At that time, such close cooperation between experimentalists and theorists was uncommon. Their collaboration resulted in a “much clearer and advanced understanding of how the nature of defect states formed at interfaces influenced their performance, well before this type of partnership between experimentalists and theorists became standard,” Tuller stated.
Johnson’s main computational tool was yet another advancement, known as the scattered wave method (also referred to as Xα multiple scattering). Though the technique has origins in mid-20th century quantum chemistry and condensed matter physics, Johnson was a prominent figure in adapting it for materials applications.
Brian Ahern PhD ’84, a former student of Johnson, remembers the strength of his approach. In 1988, while assessing whether certain superconducting materials could be utilized in a next-generation supercomputer for the Department of Defense, Ahern interviewed leading scientists across the nation. Most provided optimistic assessments — except Johnson. Based on profound theoretical calculations, Johnson demonstrated that the zero-resistance conditions required for such a machine were not realistically attainable with the existing materials.
“I communicated Johnson’s conclusions, leading to the abandonment of the Pentagon program, which saved millions of dollars,” Ahern notes.
From superconductors to screenplays
Johnson retained a strong interest in superconductors. These materials can transmit electricity without energy loss, making them vital to technologies such as MRI machines and quantum computers. However, they usually operate at cryogenic temperatures, requiring expensive equipment. When scientists uncovered so-called high-temperature superconductors — materials that function at relatively higher, but still extremely low (-300 degrees Fahrenheit), temperatures — a global competition began to decipher their behavior and search for superconductors capable of functioning at room temperature.
Utilizing the theoretical tools he had previously established, Johnson suggested that vibrations of small molecular units were the key to superconductivity — a deviation from traditional beliefs about the factors behind superconductivity. In a 1992 paper, he demonstrated that the model could apply to a variety of materials, including ceramics and buckminsterfullerene, commonly referred to as buckyballs because its molecules resemble the geodesic domes created by architect Buckminster Fuller. Johnson forecasted that room-temperature superconductivity was improbable, as the materials necessary to sustain it would be too unstable for reliable operation.
That didn’t prevent him from envisioning scientific breakthroughs in his fictional works. A consulting trip to Russia following the collapse of the Soviet Union sparked Johnson’s passion for screenwriting. Among his screenplays was “Breaking Symmetry,” featuring a young astrophysicist at a fictionalized MIT who uncovers secret research on a revolutionary energy technology. When a Hollywood production deal fell through, Johnson opted to finance and direct the film himself — even creating its special effects.
Even after his early retirement from MIT in 1996, Johnson continued his research endeavors. In 2021, he published a paper on water nanoclusters in space and their potential role in the origins of life, proposing that their characteristics could help clarify cosmic phenomena. He also employed his analytical methods to propose visual, water-based representations for dark matter and dark energy — what he termed “quintessential water.”
In his later years, Johnson developed a growing interest in conveying scientific concepts through imagery and intuition rather than complex equations, believing that nature should be comprehensible without advanced mathematics, Amacher-Johnson states. He embraced multimedia and emerging digital technologies — including artificial intelligence — to disseminate his ideas. Several of his presentations can be found on his YouTube channel.
“He never restricted himself to a solitary discipline,” Amacher-Johnson clarifies. “Physics, chemistry, biology, cosmology — all were essential parts of his integrated vision of comprehending the universe.”
In addition to Amacher-Johnson, Johnson is survived by his daughter.