Fig. 1. Sample of HfO2 (15 nm)/Co (15 nm)/HfO2 (30 nm)/Ag (40 nm). (a) Atomic force micrograph of the sample after magnetron sputtering; (b) 3D surface profile of the array; (c) Kerr hysteresis loop of the thin film; (d) schematic of p-polarized light incidence to surface of the nanocorrugation array, PR stands for photoresist

Fig. 2. Longitudinal Kerr spectra and reflectivity of the three samples with different stripe widths when the stripes’ direction is perpendicular to the incident plane. (a) Longitudinal Kerr spectra; (b) reflection spectra

Fig. 3. Distribution of electric field intensity Ez for cutting cross section (z-x coordinate plane). (a) With the stripe width of 160 nm; (b) with the stripe width of 180 nm. The incident wavelength is λ=537 nm, the incident angle is 45°

Fig. 4. Longitudinal Kerr spectra and reflectivity for the two samples with different thicknesses of HfO2 when the stripes’ direction is perpendicular to the incident plane. (a) Longitudinal Kerr spectra; (b) reflection spectra

Fig. 5. Polar Kerr spectra and reflection spectra of the samples with different intermediate layers’ thicknesses of HfO2. (a) Polar Kerr spectra; (b) reflection spectra

Fig. 6. Distribution of normalized electric field intensity E/E0 in the cutting cross section parallel to z-x plane. (a) HfO2 (15 nm)/Co (15 nm)/HfO2 (15 nm)/Ag (40 nm); (b) HfO2 (15 nm)/Co (15 nm)/HfO2 (45 nm)/Ag (40 nm)

Fig. 7. Transverse Kerr spectra and reflection spectra. (a) Transverse Kerr spectra; (b) reflection spectra