Local Electron-Lattice Interactions in High-Temperature Cuprate Superconductors

Figure 2

Magnetization curves near 𝑇_𝑐, showing the SOIE in optimally doped YBa₂Cu₃O_7−𝛿 for 𝑥 = 6.957(2) (triplet A) and 𝑥 = 6.963(3) (triplet B). Here 𝑝, 𝑎, and 𝑐 denote the different oxygen ion sites in YBa₂Cu₃O_7−𝛿 (𝑝: planar oxygen ion sites; 𝑎: apical oxygen ion sites; 𝑐: chain oxygen ion sites). For example, ⟨¹⁸O_𝑝¹⁶O_𝑎𝑐⟩^B denotes a sample from batch B with ¹⁸O in CuO₂ planes and ¹⁶O in the apical and chain sites. It is evident that the planar oxygen atoms mainly contribute to the total OIE on 𝑇_𝑐, after [55].

(a)

(b)