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Updated: May 5, 2026
Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
RKKY interactions and the anomalous Hall effect in metallic rare-earth pyrochlores
SungBin Lee1, Arun Paramekanti, Yong Baek Kim
1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada.
Abstract:
Motivated by experiments on Pr2Ir2O7, we consider metallic pyrochlore systems A2B2O7, where the A sites are occupied by rare-earth local moments and the B sites host 5d transition metal ions with itinerant strongly spin-orbit coupled electrons. Assuming non-Kramers doublets on the A site, we derive the RKKY interaction between them mediated by the B-site itinerant electrons and find extended non-Heisenberg interactions. Analyzing a simplified model of the RKKY interaction, we uncover a local moment phase with coexisting spiral Ising-like magnetic dipolar and XY-like quadrupolar ordering. This state breaks time-reversal and lattice symmetries, and reconstructs the B-site electronic band structure, producing a Weyl metallic phase with an intrinsic anomalous Hall effect and an undetectably small magnetization. We discuss implications of our results for Pr2Ir2O7.
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