Journal of Low Temperature Physics

, Volume 89, Issue 5–6, pp 869–884 | Cite as

Effects of superconducting fluctuations on the NMR relaxation rateT 1 −1 of two-dimensional systems aboveT c

  • Jürgen Heym
Article

Abstract

Fluctuation-induced corrections to the NMR relaxation rate T 1 −1 in dirty two-dimensional superconductors above the superconducting transition (T>Tc) are re-investigated including dynamic fluctuations. Static fluctuations, as discussed by Kuboki and Fukuyama,1 dominate the fluctuation terms near Tc. We find that dynamic fluctuations become important for T/Tc≳1.05, and might even reverse the sign of the total fluctuation-induced contributions to T 1 −1 . We observe that (T1T)−1 has a minimum at T=Tmin (·) for ·/Tc≳0.1 which depends on the pair-breaking parameter ·. Furthermore, we show that the fluctuation contributions to T 1 −1 can be obtained numerically with very high accuracy from multipoint Padé approximants.

Keywords

Magnetic Material Relaxation Rate Static Fluctuation Dynamic Fluctuation Fluctuation Term 

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Copyright information

© Plenum Publishing Corporation 1992

Authors and Affiliations

  • Jürgen Heym
    • 1
  1. 1.Physikalisches InstitutUniversität BayreuthBayreuthGermany

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