Fig. 4: Orientation analysis of a single NaYF4:Eu nanorod by area under curve ratiometry (AUCR).
From: Measuring 3D orientation of nanocrystals via polarized luminescence of rare-earth dopants
a Reference emission spectra of the photoluminescence (PL) of a NaYF4:Eu nanorod polarized parallel (Iπ) and perpendicular (Iσ) to the rod axis and (b) experimental spectra (Izx, Izy) of the nanorod with an orientation θ′, φ′ (also shown in Fig. 3d, e). The selected wavelength ranges (MD1, MD2, ED1, and ED2) used for AUCR are highlighted in different colors, from which the values of the trigonometric functions of (θ, φ) and the absolute values of (θ′, φ′) were calculated using Eqs. 8–13. The results of the same AUCR analysis for a large number of particles are shown in the Supplementary Data 1. c–e Polar diagrams and fitting curves of the selected areas under curve for (c) MD1 and MD2, (d) ED1 and ED2, and (e) their ratios MD1/MD2 and ED1/ED2.
