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One striking consequence of superconductivity is the Meissner effect, in which the ability of a superconductor to expel magnetic fields from its interior is used to levitate a magnet above a superconducting disk.

Superconductivity is one of the more striking physical phenomena in condensed matter physics. As metallic samples are cooled, the electrons within move more slowly and become more and more ordered. In many materials, the system can enter a new ground state at very low temperatures, a state where the entire population of electrons exists in a highly correlated state that takes advantage of the coupling between negatively charged electrons and the positively charged background lattice.

Publications

«  1992 · 1993 · 1994 · 2000 · 2003 · All
J. E. Han, O. Gunnarsson and V. H. Crespi, "Strong Superconductivity with Local Jahn-Teller Phonons in C60 Solids," Phys. Rev. Lett. 90, 167006 (2003) Abstract/Comments
V. H. Crespi, "Superconductors: Clathrates join the covalent club," Nature Mater. 2, 650 – 651 (2003) Abstract/Comments
V. H. Crespi and M. L. Cohen, "Validity of the BCS model Hamiltonian in the limit of small sizes," Phys. Rev. B 62, 8669 – 8670 (2000)
J. M. Louis, G. Choteau, Y. Ksari, G. Martinez, J. G. Hou, V. H. Crespi, X. D. Xiang, W. A. Vareka, G. Briceno, A. Zettl and M. L. Cohen, "Superconducting properties of K3C60 and Rb3C60 single crystals in high fields," Mol. Cryst. Liq. Cryst. 244, A333 – A338 (1994)
B. Burk, V. H. Crespi, M. S. Fuhrer, A. Zettl and M. L. Cohen, "Alkali-metal isotope effect in Rb3C60 (International Conference on Materials and Mechanisms of Superconductivity-- High Temperature Superconductors IV, Grenoble, France, 5-9 July 1994)," Physica C 235, 2493 (1994)
J. G. Hou, X. D. Xiang, V. H. Crespi, M. L. Cohen and A. Zettl, "Magnetotransport in single crystal Rb3C60," Physica C 228, 175 – 178 (1994) Abstract/Comments
X. D. Xiang, J. G. Hou, V. H. Crespi, A. Zettl and M. L. Cohen, "Three-dimensional fluctuation conductivity in superconducting single crystal K3C60 and Rb3C60," Nature 361, 54 – 56 (1993)
V. H. Crespi and M. L. Cohen, "Anharmonic phonons and high-temperature superconductivity," Phys. Rev. B 48, 398 – 406 (1993) Abstract/Comments
V. H. Crespi, D. R. Penn and M. L. Cohen, "Inverse isotope effects and models for high-Tc superconductivity," Phys. Rev. B 47, 5528 – 5531 (1993) Abstract/Comments
J. G. Hou, V. H. Crespi, X. D. Xiang, W. A. Vareka, G. Briceno, A. Zettl and M. L. Cohen, "Determination of superconducting and normal state parameters of single crystal K3C60," Solid State Commun. 86, 643 – 646 (1993) Abstract/Comments
V. H. Crespi and M. L. Cohen, "Anharmonic phonons and site selective isotope effects in YBa2-xMxCu3O7 (M=La, Sr)," Solid State Commun. 86, 161 – 164 (1993)
V. H. Crespi, J. G. Hou, X. D. Xiang, M. L. Cohen and A. Zettl, "Electron-scattering mechanisms in single-crystal K3C60," Phys. Rev. B 46, 12064 – 12067 (1992)
V. H. Crespi and M. L. Cohen, "Anharmonic phonons and superconductivity in PdH (D)," Solid State Commun. 83, 427 (1992) Abstract/Comments
V. H. Crespi and M. L. Cohen, "Possible discrepancies between transport and superconducting electron-phonon coupling due to anisotropic Fermi surface nesting," Solid State Commun. 81, 187 – 190 (1992) Abstract/Comments
V. H. Crespi and M. L. Cohen, "Anharmonic phonons and the anomalous isotope effect in La2-xSrxCuO4," Phys. Rev. B 44, 4712 – 4715 (1991) Abstract/Comments
V. H. Crespi, M. L. Cohen and D. R. Penn, "Anharmonic phonons and the isotope effect in superconductivity," Phys. Rev. B 43, 12921 – 12924 (1991)

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

V. H. Crespi : Superconductivity