Magnetic phase evolution in the spinel compounds Zn$_{1-x}$Co$_x$Cr$_2$O$_4$

Brent C. Melot; Jennifer E. Drewes; Ram Seshadri; Arthur P. Ramirez

doi:10.1088/0953-8984/21/21/216007

paper

Magnetic phase evolution in the spinel compounds Zn $_{1 - x}$ Co $_{x}$ Cr $_{2}$ O $_{4}$

arXiv:0808.3789 · doi:10.1088/0953-8984/21/21/216007

Abstract

We present the magnetic properties of complete solid solutions of ZnCr $_{2}$ O $_{4}$ and CoCr $_{2}$ O $_{4}$ : two well-studied oxide spinels with very different magnetic ground states. ZnCr $_{2}$ O $_{4}$ , with non-magnetic $d^{10}$ cations occupying the A site and magnetic $d^{3}$ cations on the B site, is a highly frustrated antiferromagnet. CoCr $_{2}$ O $_{4}$ , with magnetic $d^{7}$ cations (three unpaired electrons) on the A site as well, exhibits both Néel ferrimagnetism as well as commensurate and incommensurate non-collinear magnetic order. More recently, CoCr $_{2}$ O $_{4}$ has been studied extensively for its polar behavior which arises from conical magnetic ordering. Gradually introducing magnetism on the A site of ZnCr $_{2}$ O $_{4}$ results in a transition from frustrated antiferromagnetism to glassy magnetism at low concentrations of Co, and eventually to ferrimagnetic and conical ground states at higher concentrations. Real-space Monte-Carlo simulations of the magnetic susceptibility suggest that the first magnetic ordering transition and features of the susceptibility across $x$ are captured by near-neighbor self- and cross-couplings between the magnetic A and B atoms. We present as a part of this study, a method for displaying the temperature dependence of magnetic susceptibility in a manner which helps distinguish between compounds possessing purely antiferromagnetic interactions from compounds where other kinds of ordering are present.

10 pages, 5 figures, 1 table

Magnetic phase evolution in the spinel compounds Zn1−x​Cox​Cr2​O4​

Abstract

References in corpus (7)

Magnetic phase evolution in the spinel compounds Zn $_{1 - x}$ Co $_{x}$ Cr $_{2}$ O $_{4}$