Figure 5

Reflectance spectra for \(({\text {B}}{\text {T}}{\text {O}}/{\text {Y}}{\text {B}} {\text {C}}{\text {O}})_{{\text {N}}}/{\text {S}}{\text {T}}{\text {O}}\) 1D PCs for periods \(N= 1\) (a), 3 (b), and 5 (c), at \(T=20\, {\hbox {K}}\), in the 500–800 nm spectral band.