Thallium-doped BaFe$_{\mathrm{2}}$As$_{\mathrm{2}}$ crystals: The unusual competition between magneto-elastic coupling and charge doping
ORAL
Abstract
We partially substitute thallium for barium and report the effects of interlayer coupling in Ba$_{\mathrm{1-x}}$Tl$_{\mathrm{x}}$Fe$_{\mathrm{2}}$As$_{\mathrm{2}}$ crystals. We demonstrate the unusual competition between magneto-elastic coupling and charge doping in an iron-arsenide material, whereby $T_{N}$ temperature rises in BaFe$_{\mathrm{2}}$As$_{\mathrm{2}}$, and then falls with additional Tl-doping. Evidence from temperature-dependent bulk thermodynamic and transport properties, and neutron diffraction results will be presented. Using LDA, we illustrate that small changes related to 3$d$ transition-metal state can have profound effects on magnetism.
*The work is supported by the U.S. DOE, Office of Science, BES, Materials Sciences and Engineering Division, and Chemical Sciences, Geosciences, and Biosciences Division. The work at ORNL’s HFIR is sponsored by the Scientific User Facilities Division.
–