Fig. 2: Magnetic phase transition in 100 nm and 30 nm (111) Y₂Ir₂O₇ films.

Resonance profiles of the magnetic (0 0 10) reflection near Ir L₃ edge in the σ−π channel for (a) 100 nm and (b) 30 nm Y₂Ir₂O₇ films. A special azimuthal alignment which includes setting the [110] axis of the Y₂Ir₂O₇ films perpendicular to the scattering plane allows for effectively suppressing the ATS contribution and leaving the RMS signal dominant in the σ−π channel³². Peak A at 11.215 keV represents the RMS signal, which is significantly enhanced at 5 K in the long-range antiferromagnetic state. Peak B at 11.22 keV is due to the leakage of ATS that is dominant in the σ−σ channel. c Temperature dependence of the integrated intensity of magnetic (0 0 10) reflection for 100 nm (red) and 30 nm (blue) Y₂Ir₂O₇ films. The transition temperature T_N ≈ 140 K and the critical exponent β ≈ 0.30 of 100 nm sample are extracted from the data following the relationship \(I\propto {M}^{2}\propto {(1-\frac{T}{{T}_{N}})}^{2\beta }\). The error bars refer to the standard deviation of the integrated intensity calculated with a Gaussian function. d Temperature dependence of the resistivity of 100 nm (red) and 30 nm (blue) samples, which exhibit a “kink” behavior at around 145 K and 135 K, respectively. The black dashed lines are power-law fits (ρ ∝ T^−α) of the data between 100 and 20 K, with the power index α ∼ 1.3 (1.4) for 100 nm (30 nm) sample.