Nuclear Magnetic Resonance in Heavy Fermion Systems
Heavy-fermion (HF) systems discovered in rare-earth or actinide intermetallic compounds have been the intriguing subject of experimental [1,2,3] and theoretical  investigations. At low temperature, these systems having very large specific-heat coefficient and Pauli like susceptibility are characteristic of a strongly interacting electronic fermi liquid with heavy effective mass, which is derived from 4f- or 5f-electrons behaving as localized electrons at high temperature. It has become increasingly evident that the system has a new and unique ground state. The most outstanding and fascinating aspect is the fact that the compounds such as CeCu2Si2 , UBe13  and UPt3  exhibit a transition to the superconducting state. The superconducting properties are unusual, indicating that the heavy electrons are responsible for the superconductivity. Considerable amounts of experimental evidences, which conflict with the conventional theory, have suggested that the energy gap in these compounds is anisotropic, vanishing at points or lines on the Fermi surface [8,9,10,11]. First, these compounds have been discussed in analogy to superfluid 3He-A phase where the gap zeros of points are associated with the anisotropic triplet Cooper pairing. Subsequently, there have been many experimental and theoretical investigations to gain an insight into the nature and the mechanism of Cooper pairing of HF superconductor.
KeywordsFurnace Anisotropy Boron Coherence Nitride
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- F. Steglich, Theory of Heavy Fermions and Valence Fluctuations, edts. T. Kasuya and T. Saso (Springer-Verlag, 1985) p. 23.Google Scholar
- C.M. Varma, Comments Solid State Phys. 11 (1985) 221Google Scholar
- P.A. Lee, T.M. Rice, J.W. Serene, L.J. Sham and J. W. Wilkins, Comments Cond. Mat. Phys. 12 (1986) 99.Google Scholar
- G.R. Stewart, Z. Fisk and M.S. Wire, Phys. rev. B30 (1984) 482.Google Scholar
- J.J.M. Franse, P.H. Frings, A. de Visser, A. Menovsky, T.T.M. Palstra, P.H. Kes and J.A. Mydosh, Physica 126B (1984) 116.Google Scholar
- L.C. Gupta, D.E. MacLaughlin, Cheng Tien, C. Godart, M.A. Edwards and R.D. Parks, Phys. Rev. B28 (1983) 3637.Google Scholar
- Y. Kitaoka, K. Fujiwara, S. Hiramatsu, K. Asayama, Y. Onuki and T. Komatsubara, unpublished.Google Scholar
- J. Aarts, F.R. deBoer and D.E. MacLaughlin, Physica 121B (1983) 162.Google Scholar
- K. Ueda, Y. Kitaoka, H. Yamada, Y. Kohori, T. Kohara and K. Asayama, to be published in J. Phys. Soc. Jpn.Google Scholar
- Y. Kohori, T. Kohara, T. Kaneko, Y. Oda, Y. Kitaoka and K. Asayama, unpub1ished.Google Scholar