Fig. 2: Fabrication and characterization of the CrSBr metasurface.

a Optical image of mechanically exfoliated CrSBr flake. The crystallographic axis is marked. b The AFM image of the CrSBr flake. The height profile is shown as red line. c PL spectra as the function of the detection linear polarization angle \(\phi\) with respect to the \(b\)-axis. d PL peak position of a 150-nm CrSBr flake is plotted as function of FP cavity mode number. The peak position fits to the simulated EP energy using coupled oscillator model (red dashed line). The energy of excitonic states (X^* and X) and cavity is also shown. e Top and side view SEM images of a CrSBr metasurface. f, g are the measurement and simulation of Angle-resolved reflectance spectra from the CrSBr gratings with grooves parallel to \(b\)-axis. The measurements are carried out for s polarized configuration. The PL and reflectance measurement are carried out at 10 K. The scale bars in (a, b and e) are 50 µm, 3 µm and 1 µm respectively.