From phase- to amplitude-fluctuation driven superconductivity in systems with precursor pairing

  title={From phase- to amplitude-fluctuation driven superconductivity in systems with precursor pairing},
  author={J. Ranninger and L. Tripodi},
  journal={Physical Review B},
The change-over from phase- to amplitude-fluctuation-driven superconductivity is examined for a composite system of free electrons (fermions with concentration ${n}_{F})$ and localized electron pairs (hard-core bosons with concentration ${n}_{B})$ as a function of doping\char22{}changing the total concentration of charge carriers ${(n}_{\mathrm{tot}}{=n}_{F}{+2n}_{B}).$ The coupling together of these two subsystems via a charge exchange term induces electron pairing and ultimately… Expand
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