Universal $\sqrt{2}\times \sqrt{2}$ structure and short-range charge order at the surfaces of BaFe${}_{2-x}$Co${}_x$As${}_2$ compounds with various Co doping levels

Hui Zhang, Jun Dai, Yujing Zhang +7

The structure and electronic order at the cleaved (001) surfaces of the newly-discovered pnictide superconductors BaFe${}_{2-x}$Co${}_x$As${}_2$ with x ranging from 0 to 0.32 are sys…