3$d$ - 4$d$ hybridization anomaly in Ni$_x$Pd$_{1-x}$ alloys at quantum critical point

P. Swain; Sanjeev K. Srivastava; Suneel K. Srivastava

doi:10.1016/j.ssc.2017.05.008

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arXiv · 1703.09967

3$d$ - 4$d$ hybridization anomaly in Ni$_x$Pd$_{1-x}$ alloys at quantum critical point

P. Swain·Sanjeev K. Srivastava·Suneel K. Srivastava

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Abstract

$First-principles$ density functional theory computations of electronic structure and local magnetic properties of the non-fluctuating ground state of Ni$_x$Pd$_{1-x}$ alloy system around its quantum critical point $x_c = 0.026$ have been performed. The density of states at the Fermi energy and certain other parameters characterizing the Ni 3$d$ - Pd 4$d$ hybridization apparently follow power-laws with $x$ similar to that obeyed by the reported ferromagnetic to paramagnetic transition temperature. The width of Pd $4d$ density of states (DOS) and centroid of Ni 3$d$ DOS show peak-like anomalies in the neighbourhood of $x_c$, and so indicate a possible scenario of the existence of a definite relation between the orbital hybridization and the emergence of quantum fluctuations in the system.

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P. Swain, Sanjeev K. Srivastava, Suneel K. Srivastava. 2017-03-29. 3$d$ - 4$d$ hybridization anomaly in Ni$_x$Pd$_{1-x}$ alloys at quantum critical point. https://doi.org/10.1016/j.ssc.2017.05.008

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