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Schlagwörter:
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Zusammenfassung:
Both magnetic and superconducting characteristics of the new heavy
fermion superconductors (HFS), UNi2Al3 and UPd2Al3 have been
investigated extensively by means of Al-27 NMR and NQR. Systematic
studies of the nuclear-spin-lattice relaxation time T1, the Knight shift
and the spectrum of Al-27 have revealed different types of magnetic
fluctuations and spin structure between these two compounds. UNi2Al3
shows a band-type itinerant antiferromagnetic behavior, while UPd2Al3
belongs to a heavy fermion antiferromagnet with an ordinary size of
U-derived moment. In the superconducting state, the relaxation behavior
in UPd2Al3 is similar to those observed in the other HFS reported so
far, providing an evidence for an unconventional anisotropic
superconductivity with line of gap zeros on the Fermi surface as well.
Knight shift has been found to decrease considerably below T(c), showing
that the pseudo spin is well defined, not affected by the impurity
scattering.