Symmetry breaking of in-plane anisotropic magnetoresistance with temperature in La-doped Sr<sub>2</sub>IrO<sub>4</sub> film
ORAL
Abstract
Electron-doped Sr2IrO4 has been the subject of recent attention because of its similarities with hole-doped La2CuO4. However, direct evidence of its superconductivity has not yet been observed, which has led to various unresolved issues related to this material. In this study, a 14-nm thick La-doped Sr2IrO4 film was grown on a (001) SrTiO3 substrate. We found that the fourfold component of the in-plane anisotropic magnetoresistance disappears and is replaced by a twofold symmetry as the temperature increases. Variable-temperature x-ray diffraction and spatially resolved optical second-harmonic generation experiments eliminate the possibility of crystal structural distortion. The temperature dependence of direct current magnetization measurements indicates that a change in the spin structure may account for the symmetry breaking, similar to the nematic ordering of iron-based and other superconductors. These provide a perspective on these materials that helps elucidate the nature of magnetic interactions and explores the expected superconductivity of iridates.
*the National Natural Science Foundation of China (Grants No. 11674031, No. 11474022, No. 11474024, No. 11422430, and No. 11374035), the National Basic Research Program of China (Grants No.2014CB920903 and No.2013CB921701)
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Presenters
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Mingrui Liu
- Beijing Normal Univ