Magnetic excitations as driving force of superconductivity in CeCu2Si2
نویسنده
چکیده
Coexistence or competition of superconductivity and magnetic order remains an important issue in condensed matter physics. While conventional superconductivity is generally incompatible with magnetism, the magnetic 4f or 5f moments in heavy-fermion superconductors play a crucial role for the appearance of unconventional superconductivity. Similar to the high-temperature cuprate superconductors, spin excitations instead of phonons are thought to be involved in the formation of Cooper pairs. However, no common consensus exists about the magnetic origin of Cooper pairing in unconventional superconductors.
منابع مشابه
Coexistence of Superconductivity and Antiferromagnetism in Heavy-Fermion Superconductor CeCu2(Si1−xGex)2 Probed by Cu-NQR
We report on the basis of Cu-NQR measurements that superconductivity (SC) and antiferromagnetism (AF) coexist on a microscopic level in CeCu2(Si1−xGex)2, once a tiny amount of 1%Ge (x = 0.01) is substituted for Si. This coexistence arises because Ge substitution expands the unit-cell volume in nearly homogeneous CeCu2Si2 where the SC coexists with slowly fluctuating magnetic waves. We propose t...
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