Spin-lattice order in frustrated ZnCr2O4

Embargo until
Date
2009-07-17
Journal Title
Journal ISSN
Volume Title
Publisher
American Physical Society
Abstract
Using synchrotron x-ray and neutron diffraction, we disentangle spin-lattice order in highly frustrated ZnCr2O4 where magnetic chromium ions occupy the vertices of regular tetrahedra. Upon cooling below 12.5 K the quandary of antialigning spins surrounding the triangular faces of tetrahedra is resolved by establishing weak interactions on each triangle through an intricate lattice distortion. However, the resulting spin order is not simply a NeĀ“el state on strong bonds, but rather a complex coplanar spin structure, indicating that antisymmetric and/or further neighbor exchange interactions also play a role as ZnCr2O4 resolves conflicting magnetic interactions.
Description
Keywords
spin-lattice order, magnetic chromium ions, regular tetrahedra vertices, triangular faces, antialigning spins, intricate lattice distortion, zinc compounds, X-ray diffraction, neutron diffraction, Neel temperature, magnetic structure, exchange interactions (electron), antiferromagnetic, spin structure, crystal structure, ZnCr2O4
Citation
Source: Physical Review Letters 17 July 2009, vol.103, no.3, 037201 (4 pp.