Non-Fermi liquid regime in metallic pyrochlore iridates: Quantum Griffiths singularities

  title={Non-Fermi liquid regime in metallic pyrochlore iridates: Quantum Griffiths singularities},
  author={Bikas Ghosh and Vinod Kumar Dwivedi and Soumik Mukhopadhyay},
  journal={Physical Review B},
We investigate the interplay of Kondo and Ruderman-Kittel-Kasuya-Yosida coupling in the presence of disorder by chemically substituting local moment ${\mathrm{Cr}}^{3+}$ at the Ir sublattice in the metallic ${\mathrm{Pr}}_{2}{\mathrm{Ir}}_{2}{\mathrm{O}}_{7}$. We find evidence of non-Fermi liquid behavior in the transport and thermodynamic measurements at low temperature. Specifically, the magnetic susceptibility exhibits power law divergence at $T=0$. The nonanalytic temperature and magnetic… 

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