Alan j. Heeger, Professor of Physics and Professor of Materials at the University of California at Santa Barbara, Chief Scientist of UNIAX Corporation and winner of the Nobel Prize for Chemistry in 2000, had "no concept that one could make a career of science" until he reached university. An interest in physics -" it was really mysterious and difficult, and I felt there must be a way to understand this" - had initially pointed towards a career as an engineer. However, Heeger realized, once at university in Nebraska, that engineering wasn't for him - but that career as a research scientist was. Physics and math were always his preferred subjects - Heeger only took one course in chemistry and still worries that students may ask a chemistry question that he can't answer.
As a graduate student at Berkeley, Heeger studied antiferromagnetism in single crystals of transition metal fluorides. "Not only very different in terms of materials," says Heeger, "but also intellectually far removed from the electronic and optical properties of semiconducting and metallic polymers."
His move to the University of Pennsylvania as assistant professor in 1962 took him a step closer. Still related to magnetism, Heeger had become interested in the many body physics of metals. "The big problem in physics in the '70s was the metal-insulator transition - how electrons could be set free or localized - in metals," explains Heeger. He turned to organic materials - exploiting the chainlike structure of polymers to act as a model one-dimensional 'laboratory' to study the problem.
At the same time, Heeger was spending his Saturday mornings throwing ideas around with a chemistry professor then also at Pennsylvania - Alan MacDiarmid. Struggling with the interdisciplinary aspect of working together, Heeger was trying to explain the concept of the metal insulator transition using a linear chain of C-H units as a model. As any chemist knows, of course, this is the structure of polyacetylene. MacDiarmid took off for a conference in Japan with their blackboard discussions still fresh in his mind. He also took with him a sample of the metallic looking inorganic polymer, poly(sulfur nitride), with which he and Heeger were experimenting. After his talk, a young Japanese chemist, Hideki Shirakawa, approached him and showed MacDiarmid the thin films of polyacety[ene that he had grown - also with a teU-tale metal-like appearance.
After persuading Shirakawa to join them in Pennsylvania, the three continued their experiments with polyacetylene. "The idea of doping came naturally," says Heeger. Shirakawa suspected that doping would change the optical properties, so it made sense to measure conductivity as welL But no one could have predicted what came next. Taking the measurements in Heeger's laboratory, they found that the conductivity had increased by a factor of 10 million. The fruits of this collaboration were realized in the seminal paper of 1977 [J. Chem. Soc Chem. Comm. (1977) 579] and ultimately the biggest prize in science - the Nobel.
One of the lessons to be learned from all this is the importance of collaboration. "We pioneered the idea of interdisciplinary research," says Heeger. "But now it's the preferred way to go." It's not an easy option, however. "It requires reaching out and learning a new language," explains Heeger. "Working at the edge of what you know can be dangerous. And it takes generosity - you've got to take the time to teach and learn and interact." But he emphasizes that it's important to walk before you run. "It's important for a young scientist to be deeply devoted to one area, before moving out. If you don't have a sound grasp of your area, then you won't have the intuition to judge right from wrong scientifically." The other crucial factor for success, says Heeger, is "a taste for problems." And to remember that "it is not more work or more difficult to solve 'important' questions."
An important problem, good judgement and the best colleagues led Heeger to the ultimate prize. "Elation does not even come close to describing the feeling," says Heeger. "Like being a rock star!" After a lifetime of research, Heeger remains enthusiastic about all there is still to come. "There are wonderful advances in astrophysics and molecular biology which are changing the ways we look at ourselves. But it's also wonderful to see the robustness of the physics and chemistry of materials, a field that continues to be amazingly creative. With the move towards nanoscience and self-assembly, this field is full of life."