X-ray-induced disordering of the dimerization pattern and apparent low-temperature enhancement of lattice symmetry in spinel CuIr$_2$S$_4$

Journal article

At low temperatures, spinel CuIr$_2$S$_4$ is a charge-ordered spin-dimerized insulator with triclinic lattice symmetry. We find that x-rays induce a structural transition in which the local triclinic structure is preserved, but the average lattice symmetry becomes tetragonal. These structural changes are accompanied by a thousandfold reduction in the electrical resistivity. The transition is persistent, but the original state can be restored by thermal annealing. We argue that x-ray irradiation disorders the lattice dimerization pattern, producing a state in which the orientation of the dimers is preserved, but the translational long-range order is destroyed.

Authors: Ishibashi, H; Koo, T; Hor, Y; Borissov, A; Horibe, Y

• Publication status: Published
• Journal: Physical Review B
• Volume: 66
• Issue: 14
• Pages: 1444241-1444244
• Publication date: 2002-09-04
• DOI: 10.1103/PhysRevB.66.144424
• EISSN: 1095-3795
• ISSN: 1098-0121
• Language: English
• Keywords: cond-mat