Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors

Jiun-Haw Chu, James G. Analytis, Kristiaan De Greve +4

Electrical resistivity measurements of detwinned single crystals of the representative iron arsenide Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ reveal a dramatic in-plane anisotropy associated…