May 31, 1931 - Birth of John Robert Scherieffer, propused his theory of superconnectivity

American physicist born in Oak Park (in the state of Illinois) on May 31, 1931. He was awarded the Nobel Prize in Physics -which he shared with his compatriots John Bardeen (1908-1991) and Leon Cooper (1930-)- in 1972, "for the joint development of the theory of superconductivity, known as the BCS theory."

His parents, John H. Schrieffer and Louis Anderson provided him with a splendid academic education from a very young age. In 1940, when he was nine years old, he moved with his entire family to Manhasset (New York), where he lived until 1947; In that year, the Schrieffers moved their domicile to Eustis (Florida), a town in which they soon stood out as prominent members of their citrus products industry.

In 1949, the young John Robert obtained a bachelor's degree from the institute of his new city (Eustis High School), where he revealed himself as an outstanding student in all disciplines related to Science and Technology. Hence, after completing this secondary education, he formalized his admission to the Massachusetts Institute of Technology, where he specialized in electronic engineering. In this center, the future Nobel laureate was attracted to Physics and, under the direction of Professor John C. Pizarrero, he did a brilliant graduation project that culminated in a bachelor's thesis focused on the structure of atoms of bodies solids.

After his successful stint at M.I.T. (Massachusetts Institute of Technology), Schrieffer enrolled in the Faculty of Physics of the University of Illinois, where he had the teaching of a great professor, John Bardeen, with whom, after many years, he would share the Nobel Prize. Incorporated, as an outstanding student, to his team of researchers, the young Schrieffer surprised his teachers and classmates with the resolution of a complicated problem about the electric current on the surface of semiconductor bodies. This contribution earned him his immediate incorporation into a program developed in the laboratory of said University, where Schrieffer, in his third year of studies, developed, together with his teacher Bardeen and a classmate, Leon Cooper, the theory of superconductivity, which was the basic topic of his doctoral thesis. Shortly after, this contribution of the three American scientists was also known as the BCS theory, a name formed from the initials of the surnames of its enunciators.

After obtaining his doctorate in 1957, John Robert Schrieffer traveled to Europe to broaden his knowledge at the University of Birmingham (United Kingdom) and, shortly after, at the Niels Bohr Institute in Copenhagen (Denmark), where he continued to develop his studies. about superconductivity. Upon his return to the United States of America, he undertook a brilliant teaching career at the University of Chicago (1957-1959), from where he went on to join the faculty of the University of Illinois (1959-1961).

In 1960, during a summer visit to the Niels Bohr Institute in Copenhagen, he became engaged to Ana Grete Thomsen, with whom he married at the end of that year. From this marriage, three children were born (Bolette, Paul, and Regina).

His teaching career continued, from 1962, at the University of Pennsylvania (in Philadelphia, Pennsylvania), where he reached the position of Professor of Physics. Many years later, he went on to teach at the University of California (Santa Barbara), where, in 1984, he was appointed Chancellor. In addition, between 1984 and 1989 he was director of the Institute of Theoretical Physics of said higher education center.

The rest of his work activity was carried out at Florida State University (which he joined in 1992) and at the National High Magnetic Field Laboratory, of which he was head. Apart from this prolific teaching and research career, Schrieffer left his scientific knowledge embodied in some works of great depth, among which it is worth remembering the one entitled Theory of Superconductivity (Theory of superconductivity, 1964), a work of obligatory presence in all faculties. Physics of the planet.

Awarded an honorary doctorate from the universities of Munich, Geneva, Pennsylvania, Illinois, Cincinnati, Tel-Aviv, and Alabama, Schrieffer was also an active member of some prestigious scientific institutions such as the American Academy of Arts and Sciences and the U.S. National Academy of Sciences, on whose boards of directors he appeared as a trustee. In addition, he belonged to the American Philosophical Society and, outside his country, to the Royal Danish Academy of Sciences and the Academy of Sciences of the USSR.

In addition to the aforementioned Nobel Prize, John Robert Schrieffer has been distinguished with other honors and awards: the Guggenheim scholarship; the Oliver E. Buckley Prize in Physics, the Comstock Prize, from the National Academy of Sciences; the John Ericsson Medal, from the American Society of Swedish Engineers; the University of Illinois Alumni Major Achievement Award; and the National Medal of Science (1984).

Schrieffer's contributions

The theory of superconductivity, enunciated by Bardeen, Cooper, and Schrieffer in 1957 - when the latter was still a mere student under the tutelage of the former - explains that, at temperatures close to absolute zero (that is, extremely low), some metals lose completely electrical resistance. None of the three scientists can empirically prove this theory -to which Schrieffer contributed a brilliant speculation that, according to his statements, occurred to him while he was traveling in the subway-; but, shortly after, the experiments of the American physicist -although of Norwegian origin- Ivar Giaver (1929- ), who applied the tunnel effect to superconductors described by the Japanese Leo Esaki (1925- ), came to confirm the certainty of the hypothesis launched by the three scientists from the University of Illinois.

Bardeen, Cooper, and Schrieffer explained the phenomenon of superconductivity utilizing pairs of associated electrons (or Cooper pairs). In the presence of conductors subjected to an electrical voltage and at temperatures close to absolute zero, these pairs remain associated, with which the electrical current persists indefinitely by superconduction, even though the electrical voltage has been removed, and as long as the temperature of the conductor does not rise until it reaches a certain value, which varies depending on the material used.

After his contributions to the development of the BCS theory, the Oak Park physicist addressed other areas of study such as superconductivity at high temperatures, electron correlation, and electron dynamics in high-intensity magnetic fields.