Lattice Instability in High Temperature Superconducting Cuprates and FeAs Systems: Polarons Probed by EXAFS

Figure 6

Mean-square relative displacement of the in-plane Cu–O bond in thin film single crystal La_1−𝑥Sr_𝑥CuO₄ (𝑥=0.15) plotted against temperature (a) and normalized temperature 𝑇/𝑇_𝑐 (b), taken from [19].

(a)

(b)