Abstract
A complete structural solution of the bilayer iridate compound Sr3Ir2O7 presently remains outstanding. Previously reported structures for this compound vary and all fail to explain weak structural violations observed in neutron scattering measurements as well as the presence of a net ferromagnetic moment in the basal plane. In this paper, we present single crystal neutron diffraction and rotational anisotropy second harmonic generation measurements unveiling a lower, monoclinic symmetry inherent to Sr3Ir2O7. Combined with density functional theory, our measurements identify the correct structural space group as No. 15 (C2/c) and provide clarity regarding the local symmetry of Ir4+ cations within this spin-orbit Mott material.
| Original language | English |
|---|---|
| Article number | 134110 |
| Journal | Physical Review B |
| Volume | 93 |
| Issue number | 13 |
| DOIs | |
| State | Published - Apr 19 2016 |
Funding
This work was supported in part by NSF Award No. DMR-1505549 (S.D.W.), as well as by the MRSEC Program of the National Science Foundation under Award No. DMR 1121053 (T.H., L.B., C.VdW.). Work at Caltech (L.Z., D.H.) was supported by ARO Grant No. W911NF-13-1-0059. Instrumentation for the SHG measurements was partially supported by ARO DURIP Award W911NF-13-1-0293 and by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (PHY-1125565) with support of the Gordon and Betty Moore Foundation through Grant GBMF1250. C.B. acknowledges support from the Caltech WAVE Fellows program. Work performed at the ORNL Spallation Neutron Source TOPAZ single-crystal diffractometer was supported by the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy, under Contract No. DE-AC05-00OR22725 with UT-Battelle, LLC.