Extended Data Fig. 4: Characterization of core-shell-shell α-HoNPs and α-ErNPs with different Yb3+ content.
a, Simplified energy level diagrams of α-HoNPs and α-ErNPs show backward energy transfer (BET) and forward energy transfer (FET) under 980 nm excitation or 655 nm excitaion. b, c, Luminescence steady-state emission spectra and intensities (insets) for α-HoNPs with increasing Yb3+ content under (b) 980 nm and (c) 655 nm excitation. Insets show the luminescence intensity. d, e, Luminescence steady-state emission spectra and intensities for α-ErNPs with increasing Yb3+ content under (b) 980 nm and (c) 655 nm excitation.
