French physicist Pierre-Gilles de Gennes received the 1991 prize for the discovery that methods developed for studying simple systems of order phenomena can be generalized for more complex forms of matter, in particular liquid crystals and polymers. He described how, for example, a heated magnet may change from a state in which all the small atomic magnets are lined up in parallel to a disordered state in which the magnets are randomly oriented.
De Gennes was born in Paris in 1932 and studied at the École Normale. From 1955–59, he was a research engineer at the Atomic Energy Centre (Saclay), working mainly on neutron scattering and magnetism. During 1959 he did postdoctoral work at Berkeley, California, and then served for two years in the French Navy. His early work involved magnetic phase transitions, but in 1961 he became assistant professor in Orsay and set up the Orsay group on super- conductors studying more complicated order phenomena – some so complex that they had stumped physicists for years. Yet de Gennes showed that phase transitions in such apparently diverse systems as magnets, superconductors, liquid crystals and polymer solutions can be described in relatively straightforward mathematical terms, earning him the soubriquet ‘the Isaac Newton of condensed matter physics’.
In 1968, he formed the liquid crystal group in Orsay. Liquid crystals had been studied as early as the 1920s but it was not until the 1960s that they began to be exploited in such everyday objects as clocks and calculators, through to today’s flat-screen TVs. In physics, liquid crystals are often used as models to test more general theories. De Gennes’ team quickly became one of the leading groups in the field, and his 1974 book The Physics of Liquid Crystals is a standard work. In 1971, he became Professor at the Collège de France, and helped form STRASACOL (a joint action of Strasbourg, Saclay and Collège de France) on polymer physics. Polymers are formed from long chains of simpler links, called monomers. De Gennes discovered that there were more similarities than had been suspected in the arrangement of polymers and the conditions that apply when a system of magnetic moments moves from order to disorder. He also established a number of polymer dynamics – predictions, regarding how polymer chains and their individual parts can move.
From 1976 to 2002, he was the director of the École de Physique et Chimie (Paris), the ‘home’ of many scientific giants. More recently, de Gennes has worked at the Institut Curie (Paris) on cellular adhesion and brain function for cancer research. He was a member of the French Academy of Sciences, Dutch Academy of Arts and Sciences, Royal Society, American Academy of Arts and Sciences, and the National Academy of Sciences, USA. Pierre-Gilles de Gennes died on May 18th 2007.
This text of the the Nobel Laureate was taken from the book: "NOBELS. Nobel Laureates photographed by Peter Badge" (WILEY-VCH, 2008).