Impurity-induced moment freezing in NaFe${}_x$Ru${}_{1-x}$O${}_2$

Abstract

We report the impact of magnetic impurity substitution on the quantum disordered magnetic ground state of NaRuO${}_2$. Local $S=5/2$ moments are introduced into the frustrated triangular lattice of $J_{eff}=1/2$ Ru moments via Fe-substitution in NaFe${}_x$Ru${}_{1-x}$O${}_2$, and the evolution of the magnetic ground state is reported. Local spin freezing associated with conventional spin glass behavior is observed upon Fe substitution, marking an impurity-induced freezing of the primarily dynamic magnetic ground state in NaRuO${}_2$. Furthermore, local Fe moments induce a Curie-Weiss magnetic behavior in the uniform magnetic susceptibility, and the local moment magnitude is best described by dynamic Ru moments polarized about impurity sites. Our results establish an impurity-doping phenomenology consistent with inherently dynamic moments in NaRuO${}_2$ that are pinned by local magnetic impurities, similar to ``swiss cheese" models of impurity-substituted copper oxides.

7 pages, 4 figures, 2 tables

References in corpus (11)

• Continuous excitations of the triangular-lattice quantum spin liquid YbMgGaO4
• Ferromagnetic cluster spin-glass behavior in PrRhSn3
• Anisotropic field-induced ordering in the triangular-lattice quantum spin liquid NaYbSe${}_2$
• Spin excitations in the frustrated triangular lattice antiferromagnet NaYbO${}_2$
• Spin Glass-like Phase below ~ 210 K in Magnetoelectric Gallium Ferrite
• Magnetic Structure and Properties of the S = 5/2 Triangular Antiferromagnet $\alpha$-NaFeO${}_2$
• Long-range magnetic order in the $\tilde{S}=1/2$ triangular lattice antiferromagnet KCeS${}_2$
• A $j_{\mathrm{eff}}=1/2$ Kitaev material on the triangular lattice: The case of NaRuO${}_2$
• NaRuO${}_2$: Kitaev-Heisenberg exchange in triangular-lattice setting
• Electronic and structural properties of RbCeX${}_2$ (X${}_2$: O${}_2$, S${}_2$, SeS, Se${}_2$, TeSe, Te${}_2$)
• Defect control in the Heisenberg-Kitaev candidate material NaRuO${}_2$