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arXiv · 2105.05149

Unified description of resistivity and thermopower of Pr$_2$Ir$_2$O$_7$: possible influence of crystal field excitation in a Kondo lattice

Bikash Ghosh·Soumik Mukhopadhyay
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Abstract

We present experimental evidence of incoherent Kondo scattering as the source of resistivity minima in bulk polycrystalline and nanocrystalline Pr$_2$Ir$_2$O$_7$. The temperature dependence of thermopower shows a positive maximum at high temperature followed by a negative minimum at low temperature, with the sign inversion occurring at a much higher temperature than $T_K$. Moreover, we observe little correlation between TK and intersite coupling strength given by $\theta_{CW}$. We describe the temperature dependence of thermopower and resistivity within the framework of crystal field excitation in a Kondo lattice.

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Bikash Ghosh, Soumik Mukhopadhyay. 2021-04-27. Unified description of resistivity and thermopower of Pr$_2$Ir$_2$O$_7$: possible influence of crystal field excitation in a Kondo lattice. https://doi.org/10.1103/physrevb.103.165135

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