The Sensitivity of the Magnetic Properties of the ZnCr2O4 and MgCr2O4 Spinels to Non-stoichiometry

Abstract

We report that small amounts of metal atom non-stoichiometry are possible in the ZnCr2O4 and MgCr2O4 spinels. The non-stoichiometry, though less than 2%, significantly impacts TN and the nature of the magnetic correlations above TN. The Zn1+xCr2-xO4 spinel is particularly sensitive. While stoichiometric ZnCr2O4 displays antiferromagnetic short range correlations in the susceptibility above TN, ferromagnetic correlations are observed in non-stoichiometric, hole doped Zn1+xCr2-xO4. The Mg1+xCr2-xO4 spinels are less profoundly affected by non-stoichiometry, though significant changes are also observed. We contrast the magnetic properties of Zn1+xCr2-xO4 and Mg1+xCr2-xO4 (x=0, 0.02, 0.04) with those of materials with the equivalent amounts of isovalent non-magnetic Ga3+ substituted on the Cr3+ site to separate the effects of static site disorder and hole doping.

21 pages, 7 figures, To be published in Physical Review B

References in corpus (4)

• Magnetic phase evolution in the spinel compounds Zn${}_{1-x}$Co${}_x$Cr${}_2$O${}_4$
• The magnetic properties of the Garnet and glass forms of Mn3Al2Si3O12
• Divergent effects of static disorder and hole doping in geometrically frustrated b-CaCr2O4
• Neel to Spin-Glass-like Phase Transition versus Dilution in Geometrically Frustrated ZnCr_{2-2x}Ga_{2x}O_4

Cited by in corpus (14)

• Magnetic excitations of the classical spin liquid MgCr2O4
• Spin liquid in a single crystal of the frustrated diamond lattice antiferromagnet CoAl2O4
• Crystal structures of spin-Jahn-Teller ordered MgCr_2O_4 and ZnCr_2O_4
• Structural distortion below the Néel temperature in spinel GeCo${}_2$O${}_4$
• Structural ground states of ($A,A^{\prime }$)Cr${}_2$O${}_4$($A$=Mg, Zn; $A^{\prime }$ = Co, Cu) spinel solid solutions: Spin-Jahn-Teller and Jahn-Teller effects
• Universal exchange-driven phonon splitting in antiferromagnets
• Manifolds of magnetic ordered states and excitations in the almost Heisenberg pyrochlore antiferromagnet MgCr2O4
• Evolution of magnetic properties in the normal spinel solid solution Mg(1-x)Cu(x)Cr2O4
• Constrained DFT+$U$ approach for understanding the magnetic behaviour of ACr${}_2$O${}_4$ (A=Zn, Mg, Cd and Hg) compounds
• Temperature evolution of the effective magnetic anisotropy in the MnCr${}_2$O${}_4$ spinel
• Ferromagnetic phase of spinel compound MgV${}_2$O${}_4$ and its spintronics properties
• Orientation-dependent stabilization of MgCr${}_2$O${}_4$ spinel thin films
• The role of ionic sizes in inducing the cubic to tetragonal distortion in AV${}_2$O${}_4$ and ACr${}_2$O${}_4$ (A=Zn, Mg and Cd) compounds
• Spin liquid state in a three-dimensional pyrochlore-like frustrated magnet