Extended Data Fig. 5: Three-dimensional phase separation in the HPO-annealed sample.
From: Interstitial oxygen order and its competition with superconductivity in La2PrNi2O7+δ
a, Projected MEP-reconstructed phase image of HPO sample as shown in Fig. 4a. b-e, Slice images extracted within the yellow dashed rectangle in panel a, from the depth range of 11-13 nm (b), 14-16 nm (c), 17-21 nm (d), and 22-24 nm (e), respectively. Panels b and c display the stage-1 order in the period-b phase, while panel e exhibits the pristine 327 phase. Panel d shows a crossover region between these two phases where octahedral distortions are not well-defined. These results provide clear evidence of a three-dimensional phase separation.
