Identification of Griffiths-like phase and its evolution in Cr substituted pyrochlore iridates $Y_{2}I{r}_2{O}_7$

Abstract

We report the Griffiths phase (GP)-like state along with cluster-glass-like state in geometrically frustrated antiferromagnetic $Cr$ substituted $Y_{2}I{r}_2{O}_7$ pyrochlore iridates. The strength of GP-like behaviour increases with substitution. Interestingly, isothermal remanent magnetization suggests the Ising-like interaction of spins in GP region. The GP-like state is not attributed to the structural disorder as substitution of Cr does not induces any structural change. Then the spin coupling between $C{r}^{3+}\leftrightarrow C{r}^{3+}$, $I{r}^{4+}\leftrightarrow I{r}^{4+}$, $I{r}^{4+}\leftrightarrow C{r}^{3+}$ and $I{r}^{4+}\leftrightarrow I{r}^{5+}$ leads the competition between antiferromagnetic and ferromagnetic correlations. It give rise to Ruderman-Kittel-Kasuya-Yosida (RKKY)-like interaction between $C{r}^{3+}$ local magnetic moments mediated by itinerant $Ir$ conduction electrons, hence, as a result GP and cluster-glass-like states emerges.

8 pages, 10 figures

References in corpus (12)

• Magnetic Order in the Pyrochlore Iridates A2Ir2O7 (A = Y, Yb)
• A New Type of Quantum Criticality in the Pyrochlore Iridates
• Enhanced weak ferromagnetism and conductivity in hole-doped pyrochlore iridate Y2Ir2O7
• Direct Evidence for the 'All-in/All-out' Magnetic Structure in the Pyrochlore Iridates from $\mu$SR
• Evolution of structure, magnetism and electronic transport in doped pyrochlore iridate Y${}_2$Ir${}_{2-x}$Ru${}_x$O${}_7$
• Identification of a Griffiths singularity in a geometrically frustrated antiferromagnet
• Magnetic and transport properties in pyrochlore iridates (Y${}_{1-x}$Pr${}_x$)${}_2$Ir${}_2$O${}_7$: The role of $f$-$d$ exchange interaction and $d$-$p$ orbital hybridization
• Colossal enhancement of electrical conductivity in Y2Ir2O7 nanoparticles
• Coexistence of high electrical conductivity and weak ferromagnetism in Cr doped Y${}_2$Ir${}_2$O${}_7$ pyrochlore iridate
• Suppression of long range magnetic ordering and electrical conduction in Y${}_{1.7}$Bi${}_{0.3}$Ir${}_2$O${}_7$ thin film
• Nonmagnetic substitution in pyrochlore iridate Y${}_2$(Ir${}_{1-x}$Ti${}_x$)${}_2$O${}_7$: Structure, magnetism and electronic properties
• Non-Fermi liquid regime in metallic pyrochlore iridates: Quantum Griffiths singularities