Fig. 3

Evolution of the PL intensity distribution over the nanowire NW#1. a PL images of the NW at different temperatures during the cooling and heating cycles; the scale bar shown in SEM image is 500 nm. b Fitting of the PL intensity distribution at 145 K along the NW (y-axis) with four Gaussian peaks representing four emitting regions of the tetragonal phase and a background (black line) coming from the orthorhombic phase (see Supplementary Note 3, Supplementary Figs. 5, 6). The violet dots represent the original data and the violet line the overall fit. c Luminescence image of the NW at 145 K showing the tetragonal domains A–C; the color chart is the same as for images in a. d, e Temperature variation of the position and the characteristic radius of the domains A–C along the y-axis as a function of temperature in the cooling cycle (Supplementary Note 4). All data points in d have the same absolute error bar ( ± 50 nm) as, for the sake of clarity, is shown for one data point only. The error bars in d, e were calculated taking into account the noise of the data and uncertainty of the fitting/deconvolution procedure