NMR/NQR Studies of Phase-Transition Precursors

  • John L. Bjorkstam
Conference paper


When the electric-field-gradient (efg) tensor at the site of a quadrupolar nucleus undergoes a substantial change at an order-disorder phase transition (temperature=TC), a very small admixture of the low-temperature order parameter into the high temperature phase can substantially influence the lineshape. Clear evidence of this effect is present in some crystals to temperatures T>3TC. It is shown that this is not an effect associated only with regions near an impurity, but is a bulk phenomenon. Temperature dependence of the lineshape above TC is related to the order parameter admixture

PACS numbers

76.60G 64.70K 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • John L. Bjorkstam
    • 1
  1. 1.Electrical Engineering, (FT-10)University of WashingtonSeattleUSA

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