Magnetic anomalies in the spin chain system, Sr${}_3$Cu${}_{1-x}$Zn${}_x$IrO${}_6$

Abstract

We report the results of ac and dc magnetization (M) and heat-capacity (C) measurements on the solid solution, Sr${}_3$Cu${}_{1-x}$Zn${}_x$IrO${}_6$. While the Zn end member is known to form in a rhombohedral pseudo one-dimensional K${}_4$CdCl${}_6$ structure with an antiferromagnetic ordering temperature of (T${}_N$ =) 19 K, the Cu end member has been reported to form in a monoclinically distorted form with a Curie temperature of (T${}_C$ =) 19 K. The magnetism of the Zn compound is found to be robust to synthetic conditions and is broadly consistent with the behavior known in the literature. However, we find a lower magnetic ordering temperature (T${}_o$) for our Cu compound (~ 13 K), thereby suggesting that T${}_o$ is sensitive to synthetic conditions. The Cu sample appears to be in a spin-glass-like state at low temperatures, judged by a frequency dependence of ac magnetic susceptibility and a broadening of the C anomaly at the onset of magnetic ordering, in sharp contrast to earlier proposals. Small applications of magnetic field, however, drive this system to ferromagnetism as inferred from the M data. Small substitutions for Cu/Zn (x = 0.75 or 0.25) significantly depress magnetic ordering; in other words, T${}_o$ varies non-monotonically with x (T${}_o$ ~ 6, 3 and 4 K for x = 0.25, 0.5, and 0.67 respectively). The plot of inverse susceptibility versus temperature is non-linear in the paramagnetic state as if correlations within (or among) the magnetic chains continuously vary with temperature. The results establish

7 pages, 7 figures, Revtex

References in corpus (3)

• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• First order transition from antiferromagnetism to ferromagnetism in Ce(Fe${}_{0.96}$Al${}_{0.04}{)}_2$
• Sr${}_3$CuIrO${}_6$, a spin-chain compound with random ferromagnetic-antiferromagnetic interactions

Cited by in corpus (12)

• Magnetic behaviour of quasi-one-dimensional oxides, Ca${}_3$Co${}_{(}1+x)$Mn${}_{1-x}$O${}_6$
• Magnetic frustration in a stoichiometric spin-chain compound, Ca${}_3$CoIrO${}_6$
• Ferromagnetic Exchange Anisotropy from Antiferromagnetic Superexchange in the Mixed 3d-5d Transition-Metal Compound Sr3CuIrO6
• Evidence for the coexistence of low-dimensional magnetism and long-range order in Ca3CoRhO6
• Heat-capacity anomalies in the presence of high magnetic fields in the spin-chain compound, Ca3Co2O6
• Magnetic susceptibility and heat capacity investigations of the unconventional spin-chain compound Sr3CuPtO6
• Long range magnetic ordering in a spin-chain compound, Ca${}_3$CuMnO${}_6$, with multiple bond distances
• Magnetic behavior of the spin-chain compounds,Ca3CuIrO6 and Ca3CuRhO6
• Non-collinear Order and Spin-Orbit Coupling in Sr${}_3$ZnIrO${}_6$
• Magnetic behavior of spin-chain compounds, Sr3ZnRhO6 and Ca3NiMnO6, from heat capacity and ac susceptibility studies
• Role of crystal field ground state in the classical spin-liquid behavior of a quasi-one dimensional spin-chain system Sr3NiPtO6
• Magnetic ground state and excitations in mixed 3$d$-4$d$ quasi-1D spin-chain oxide Sr${}_3$NiRhO${}_6$