Experimental Realisation of Tunable Ferroelectric/superconductor $$({\text {B}} {\text {T}} {\text {o}}/{\text {Y}} {\text {b}}{\text {C}} {\text {o}})_{{\text {n}}}/{\text {s}}{\text {t}}{\text {O}}$$ 1D Photonic Crystals in the Whole Visible Spectrum