Fig. 1. (a) Magnetization versus magnetic field curves at RT for all samples. (b) Magnetic hysteresis loop for 8 sccm sample at temperatures of 5 and 300 K.

Fig. 2. Wide scan XPS spectra for ZrOx films.

Fig. 3. (a) Zr 3d XPS spectra and (b) O 1s XPS spectra for ZrOx films.

Fig. 4. PL spectra of ZrOx films measured at RT. The inset shows an enlarged visible wavelength region of 450–580 nm.

Fig. 5. 2×2×2 supercell of monoclinic ZrO2. The red and cyan spheres represent the O and Zr atoms, respectively. The positions of Zr atoms substituted by O atoms are denoted by 1 and 2, while the O interstitials are marked by 3 and 4.

Fig. 6. DOS and PDOS of the (a)–(b) pure m-ZrO2, (c)–(d) 1.6%, and (e)–(f) 3% oxygen interstitial defects in m-ZrO2. The vertical dotted line stands for the Fermi level.

Fig. 7. DOS and PDOS of m-ZrO2 with OZr concentration of (a)–(b) 3%, (c)–(d) 6%, and (e)–(f) 9%. The vertical dotted line stands for the Fermi level.