BARDEEN, J., COOPER, L. & SCHRIEFFER, J. R. Theory of superconductivity.
Lancaster: American Physical Society, 1957. First edition, offprint issue.

Very rare offprint of the ‘BCS’ theory of superconductivity, the first successful quantum-mechanical explanation of the disappearance of electrical resistance in certain metals at very low temperatures. Superconductivity was first observed by Kammerlingh Onnes in 1911. “In the competitive world of theoretical physics, the BCS theory was the triumphant solution of a long-standing riddle. Between 1911 and 1957, all the best theorists in the world, among them [Richard] Feynman, Albert Einstein, Niels Bohr, Werner Heisenberg, Wolgang Pauli and Lev Landau had tried and failed to explain superconductivity” (Hoddesdon & Daitch, p. 3).

“In 1957, the Physical Review published the first fundamental theory explaining how, at low temperatures, some materials can conduct electricity entirely without resistance. Building on experimental clues and earlier theoretical hints, John Bardeen, Leon Cooper, and Robert Schrieffer, all at the University of Illinois in Urbana, explained not just the absence of electrical resistance but also a variety of magnetic and thermal properties of superconductors. The ‘BCS’ theory also had an important influence on theories of particle physics and provided the starting point for many attempts to explain the new high-temperature superconductors.

“Superconductivity was discovered in 1911, and by the 1930s, physicists had concluded that electrons in a superconductor must occupy a quantum-mechanical state distinct from that of normal conduction electrons. In 1950, researchers found that the temperature at which mercury becomes a superconductor is slightly higher for mercury isotopes of lower atomic weight, suggesting that superconductivity somehow involves motion of the atoms in a material as well as the electrons.

“Following up on this ‘isotope effect,’ Bardeen and Illinois colleague David Pines showed theoretically that within an atomic lattice, electrons could attract one another, despite their strong electrostatic repulsion. Essentially, an electron can create vibrations among the lattice atoms, which can in turn affect other electrons, so the attraction is indirect.

“By the middle 1950s, Bardeen was collaborating with Cooper, a post-doctoral fellow, and Schrieffer, a graduate student. Cooper published a short paper showing how the Bardeen-Pines attraction could cause electrons with opposite momentum to form stable pairs [L. Cooper, ‘Bound electron pairs in a degenerate Fermi gas’, pp. 1189-1190 in Physical Review, Vol. 104, November 1956]. This pairing mechanism, Cooper suggested, might be responsible for superconductivity, but Bardeen was initially sceptical. The paired electrons were not physically close together but moved in a coordinated way, always having equal but opposite momentum. It was not clear that these tenuous, extended pairs could be crammed together to create a superconducting medium without getting disrupted.

“A few months later, however, Schrieffer hit on a mathematical way of defining a quantum mechanical state containing lots of paired electrons, with the pairs oblivious to other electrons and the lattice, allowing them to move without hindrance... After publishing a short note early in 1957 [J. Bardeen, L. Cooper & J. R. Schrieffer, ‘Microscopic theory of superconductivity’, pp. 162-164 in Physical Review, Vol. 106, April 1957], the team published what became known as the Bardeen-Cooper-Schrieffer, or BCS, theory of superconductivity in December... The theory explained the isotope effect and the fact that magnetic fields below a certain strength cannot penetrate superconductors. It also explained why superconductivity could only occur near absolute zero--the tenuous Cooper pairs break up in the presence of too much thermal jiggling” (American Institute of Physics: http://prlo.aps.org/story/v18/st8)

Bardeen, Cooper and Schrieffer were awarded the 1972 Nobel Prize in Physics for this work, earning Bardeen the singular distinction of being the only person to be awarded the Nobel Prize in Physics twice. His team completed the work on superconductivity just a few months after he returned from Stockholm to collect the 1956 Prize for the invention of the transistor (shared with William Shockley and Walter Brattain).

L. Hoddesdon & V. Daitch, True Genius: The Life and Science of John Bardeen, 2002.

Offprint from Physical Review, Series II, Vol. 108, December 1957, pp. 1175-1204. 4to: 267 x 200 mm, original printed self-wrappers, signature of previous owner to front wrapper, fine condition. Very rare. The offprint is accompanied by copies of the two earlier Physical Review papers which announced the essential ideas leading to the BCS theory (each contained in a complete journal issue in the original printed wrappers).