Quenched Fe moment in the collapsed tetragonal phase of Ca1−xPrxFe2As2

  title={Quenched Fe moment in the collapsed tetragonal phase of Ca1−xPrxFe2As2},
  author={Long Ma and G. F. Ji and Jianhui Dai and S. R. Saha and Johnpierre Paglione and Weiqiang Yu},
  journal={Chinese Physics B},
We report 75As NMR studies on single crystals of rare-earth doped iron pnictide superconductor Ca1−xPrxFe2As2. In both cases of x = 0.075, 0.15, a large increase of νq upon cooling is consistent with the tetragonal-collapsed tetragonal structure transition. A sharp drop of the Knight shift is also seen just below the structure transition, which suggests the quenching of Fe local magnetism, and therefore offers important understanding of the collapsed tetragonal phase. At even low temperatures… 

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