Philip Warren Anderson Biography

The 1977 Nobel Prize in physics that Philip Warren Anderson shared with Nevill Francis Mott and John Van Vleck was given not so much for one specific discovery but for his contributions over a number of years to the study of magnetism and disordered states. In fact, Anderson's interests have extended well beyond those areas and have included work on the broadening of line spectra, electron tunneling, and superconductivity.

Philip Warren Anderson was born in Indianapolis, Indiana, on December 13, 1923, but he grew up in Urbana, Illinois. Anderson's father, Harry Warren Anderson, was a professor of plant pathology at the University of Illinois; his mother, the former Elsie Osborne, was the daughter of a professor of mathematics. Anderson graduated from University High School in Urbana in 1940 and was then awarded a scholarship to Harvard University. He graduated from Harvard with a B.S., summa cum laude, in 1943.

World War II prevented Anderson from beginning his graduate studies immediately. Instead he accepted a job at the Naval Research Laboratory in Washington, D.C., where he worked on the design of radio and radar antennae. At the war's conclusion, Anderson returned to Harvard to begin his graduate studies in physics. His doctoral advisor there was the physicist John Hasbrouck Van Vleck, later to share a Nobel Prize with Anderson.

Anderson's graduate studies focused on the problem of line spectrum broadening. The term line spectrum suggests a spectrum in which electron transitions within an atom result in the formation of clear, distinct lines. In fact, that type of event is often not the case. Interactions among atoms and among molecules often cause slight variations in the emission of energy from an atom, variations that result in a "smearing" of lines. Anderson found that modern quantum theory, which posits that energy exists in discrete units, provided a means for developing a quantitative explanation of the broadening effect. For this line of research, Anderson was awarded his M.S. degree in 1947 and then his Ph.D. in 1949 from Harvard.

Anderson's first job after graduation was with the Bell Telephone Research Laboratories in Murray Hill, New Jersey, where he was at first involved in studies on magnetism. Once again, he used the techniques of quantum mechanics to show how the properties of individual atoms and electrons could be used to explain magnetic properties on a macroscopic scale. This work was one of the fields singled out by the Nobel Prize committee in its award of the 1977 physics prize to Anderson.

In 1964 Anderson designed and carried out an experiment that demonstrated the existence of electron tunneling in semiconductors with AC currents. He also examined the effects of impurities in semiconductors, as predicted by quantum theory.

During the academic year 1953-54, Anderson was a visiting professor at the University of Tokyo. At a conference on theoretical physics held in Kyoto during the year, Anderson made the acquaintance of Nevill Mott (later, Sir Nevill Mott), an English physicist with interests similar to Anderson's. Mott suggested that Anderson visit him at his own laboratories at Cambridge University. The two eventually worked out a plan whereby Anderson could spend half of each year at Cambridge and half at the Bell Laboratories.

The topic to which Anderson and Mott devoted much of their attention was the behavior of electrons in amorphous solids. Traditionally, physicists had done most of their research on ordered solids, that is, crystals in which ions and electrons occupy relatively clearly defined positions. The mathematics of such systems, while not always simple, was at least easier than for systems in which ions and electrons are more randomly distributed through a material.

In 1958 anderson published a paper, "Absence of Diffusion in Certain Random Lattices," in which he announced a new theory of disordered solids. The behavior of electrons in such solids as well as the properties of the solid itself can best be understand, he said, by acknowledging that electrons are often "tied" to specific locations within the solid and are not free to move throughout it. This phenomenon has become known as Anderson localization and has made it possible to design materials with very specific and desirable properties. The use of relatively inexpensive amorphous silicon in place of the more expensive pure silicon in semiconductors is one example of the practical applications of Anderson's discovery. The analysis of disordered solids was the second basis for the Nobel Prize committee's decision to award the 1977 physics prize to Anderson.

Anderson commuted to Mott's laboratory from 1967 to 1975 and then abandoned that practice in order to become consulting director at Bell Labs and Joseph Henry Professor of Physics at Princeton University. He held his Bell post until his retirement in 1984, although he continued to teach at Princeton. Anderson continued his research after retirement and, in 1987, announced a new theory of superconductivity, in which he was able to explain the recent discovery of high-temperature superconducting materials.

In addition to the Nobel Prize, Anderson has been awarded the Oliver E. Buckley Prize of the American Physical Society (1964), the Dannie Heineman Prize of the Göttingen Academy of Sciences (1975), the Guthrie Medal of the London Institute of Physics (1978), and the National Medal of Science (1982).