Fig. 2: XAS and magnetic states evolution in Ru_1-xCr_xO₂ films grown on TiO₂ (110).

a XAS around the L-edge of Cr measured in the Ru_1-xCr_xO₂ films compared to that in La_1-xSr_xCrO₃²⁸. b, c Temperature-dependent magnetic susceptibility (b) and magnetic field-dependent magnetization (c) curves measured with a magnetic field along the out-of-plane (OOP) axis. All films are grown on TiO₂ (110). Inset of (b), the effective on-site moments (μ_eff) depending on the doping level x. Inset of (c), an expanded view of the low-field region. Linear fittings of the χ⁻¹–T curves at high temperatures indicate an antiferromagnetic behavior with negative Weiss temperatures θ_W = −10 K and −75 K in x = 0.1 and 0.2, respectively. The x = 0.3 film shows a small positive θ_W, with a finite remanent magnetization at zero field, implying a ferrimagnetic ground state. The magnetic field is 1 T for the χ⁻¹–T measurement.