fig5
Figure 5. Raman spectra of freestanding ferroelectric BaTiO3 (~25 nm)/BaZrO3 (~30 nm) membrane heterostructures. (A) Raman spectra of the as-integrated freestanding BaTiO3/BaZrO3 membranes heterojunctions. The vertical dashed lines mark principal BaTiO3 phonons, and a strain-responsive mode appears near ~640 cm-1. (B) Polarization-resolved spectra (parallel versus cross) highlighting selection-rule consistency and the BaTiO3 overlayer origin of the principal features.
