John Bardeen

John Bardeen (May 23, 1908 – January 30, 1991) was an American physicist who stands alone as the only person to have won the Nobel Prize in Physics twice. He shared his first award in 1956 with William Shockley and Walter Brattain for creating the transistor, and his second in 1972 with Leon Cooper and John Robert Schrieffer for the BCS theory, which explains superconductivity at a microscopic level.

Bardeen grew up in Wisconsin, where he earned both his bachelor’s and master’s degrees in electrical engineering from the University of Wisconsin. He went on to get a Ph.D. in physics from Princeton University. After serving in World War II, he worked as a researcher at Bell Labs and later became a professor at the University of Illinois.

The transistor transformed electronics, enabling nearly every modern device—from telephones to computers—and launching the Information Age. His work on superconductivity, which earned him his second Nobel, now underpins technologies like nuclear magnetic resonance (NMR) spectroscopy, medical MRI machines, and superconducting quantum circuits.

Bardeen is the first of only three people to win multiple Nobel Prizes in the same category (the others being chemists Frederick Sanger and Karl Barry Sharpless), and one of five individuals overall with two Nobel Prizes. In 1990, *Life* magazine named him one of the “100 Most Influential Americans of the Century.”

Born in Madison, Wisconsin, to Charles Russell Bardeen, the first dean of the University of Wisconsin Medical School, and Althea Harmer, he graduated from University of Wisconsin High School in 1923 at age 15. He could have finished earlier but delayed due to coursework at another school and his mother’s death. Entering the University of Wisconsin in 1923, he joined the Zeta Psi fraternity, partly funding his membership by playing billiards, and was inducted into the Tau Beta Pi engineering honor society. Choosing engineering over an academic path like his father’s, he saw better job prospects. He earned his B.S. in Electrical Engineering in 1928, taking a year off to work in Chicago but still finishing in five years instead of four to take graduate physics and math courses. He completed his M.S. in Electrical Engineering in 1929 under Leo J. Peters.

Bardeen stayed at Wisconsin briefly before working at Gulf Research Laboratories from 1930 to 1933, developing methods for interpreting magnetic and gravitational surveys as a geophysicist. When the work lost its appeal, he applied to Princeton’s graduate math program. There, he studied mathematics and physics, writing his thesis on solid-state physics under Eugene Wigner. Before finishing, he became a junior fellow at Harvard University from 1935 to 1938, working with future Nobel laureates John Hasbrouck van Vleck and Percy Williams Bridgman on cohesion and electrical conduction in metals, as well as nuclear level density. He received his Ph.D. in Mathematical Physics from Princeton in 1936.

From 1938 to 1941, he was an assistant professor at the University of Minnesota’s physics department. During World War II, from 1941 to 1944, he led a group at the Naval Ordnance Laboratory focused on magnetic mines, torpedoes, and countermeasures. During this time, his wife Jane gave birth to son Bill in 1941 and daughter Betsy in 1944.

In October 1945, Bardeen joined Bell Telephone Laboratories as part of a solid-state physics group led by William Shockley and chemist Stanley Morgan. The team also included Walter Brattain, physicist Gerald Pearson, chemist Robert Gibney, electronics expert Hilbert Moore, and several technicians. He moved his family to Summit, New Jersey. Their goal was to find a solid-state alternative to fragile glass vacuum tube amplifiers. Early attempts, based on Shockley’s idea of using an external electric field on a semiconductor to alter its conductivity, repeatedly failed. The group stalled until Bardeen proposed that surface states were blocking the field from penetrating the semiconductor. They then focused on studying these surface states, meeting almost daily and exchanging ideas freely. By winter 1946, Bardeen had enough results to submit a paper on surface states to *Physical Review*. Brattain began experiments shining bright light on semiconductor surfaces to study the states, leading to more papers—one co-authored with Shockley—estimating the surface state density was high enough to explain the earlier failures. Progress accelerated when they added electrolytes around point contacts between the semiconductor and wires. Moore built a circuit that...