Colossal enhancement of electrical conductivity in Y2Ir2O7 nanoparticles

Abstract

We present a comparative study of the magnetic and electrical properties of polycrystalline and nanocrystalline Y2Ir2O7, the latter prepared using a new chemical route. We find that reduction in particle size leads to enhanced ferromagnetism and orders of magnitude enhancement of electrical conductivity in the nanocrystalline sample. Based on x ray photoelectron spectroscopy and x ray absorption near edge structure spectroscopy results, the phenomenon is attributed to the increased fraction of pentavalent oxidation state of Iridium and the resulting increase in double exchange interaction along with the weakening of spin orbit coupling strength in the nanocrystalline sample compared to the bulk.

arXiv comment14 pages, 9 figures

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Cited by in corpus (11)

• Robust pinning of magnetic moments in pyrochlore iridates
• Negative longitudinal magnetoresistance in the density wave phase of Y${}_2$Ir${}_2$O${}_7$
• The interplay between structural, magnetic and electronic states in the pyrochlore iridate Eu2Ir2O7
• Coexistence of high electrical conductivity and weak ferromagnetism in Cr doped Y${}_2$Ir${}_2$O${}_7$ pyrochlore iridate
• Influence of electronic structure parameters on the electrical transport and magnetic properties of $Y_{2-x}B{i}_{x}I{r}_2{O}_7$ pyrochlore iridates
• Suppression of long range magnetic ordering and electrical conduction in Y${}_{1.7}$Bi${}_{0.3}$Ir${}_2$O${}_7$ thin film
• Evidence of density waves in single crystalline nanowires of Pyrochlore Iridates
• Identification of Griffiths-like phase and its evolution in Cr substituted pyrochlore iridates $Y_{2}I{r}_2{O}_7$
• Unified description of resistivity and thermopower of Pr${}_2$Ir${}_2$O${}_7$: possible influence of crystal field excitation in a Kondo lattice
• Non-Fermi liquid regime in metallic pyrochlore iridates: Quantum Griffiths singularities
• Charge density wave and Weyl Semimetal phase in Y${}_2$Ir${}_2$O${}_7$