Fig. 3
From: Cross-plane coherent acoustic phonons in two-dimensional organic-inorganic hybrid perovskites
Determination of the refractive index for N = 6. a Angular and b side-view of the examined flake taken under SEM. c Reflection spectrum and d several possible n′(λ) curves obtained using different m0 values, with the correct n′(λ) curve shown in red. The cyan dot denotes the refractive index at the absorption onset wavelength determined from a separate step
