Figure. 3.

Anisotropic charge transport in PFO nanowires. (a) A hole polaron trajectory overlaid with the local superresolution spectral map, showing two $\mathrm{\beta }$ phases segmented by torsional disorder. The color of the superresolution map indicates the peak wavelength of the local emission spectrum. Binning was performed to reduce the localization uncertainty to ~5 nm. (b, c) The emission spectrum of the regions shown in panel a, indicated by different colors. (d) The corresponding longitudinal (cyan) and transverse (dark blue) single polaron motion trajectories. The red arrow indicates a transition event between the $\mathrm{\beta }$ phases. (e) Longitudinal (blue) and transverse (green) MSD of a hole polaron trajectory, both fitted to a bi-exponential confined diffusion function. $⟨x_f^2\left(t\right)⟩=⟨x_f^2\left(0\right)⟩+L_{f1}^2\left\{1-\mathrm{e}\mathrm{x}\mathrm{p}\left(-2D_{f1}t/\right.\right.\left.\left.L_{f1}^2\right)\right\}+L_{f2}^2\left\{1-\mathrm{e}\mathrm{x}\mathrm{p}\left(-2D_{f2}t/L_{f2}^2\right)\right\}$. For longitudinal transport, $D_{f1}=4.3\times {10}^5{\mathrm{n}\mathrm{m}}^2/\mathrm{s}$, $L_{f1}=35\mathrm{n}\mathrm{m}$, $D_{f2}=8.9\times {10}^3{\mathrm{n}\mathrm{m}}^2/\mathrm{s},\mathrm{ }{L}_{f2}=85\mathrm{n}\mathrm{m}$. For transverse transport, $D_{f1}=3.7\times {10}^4{\mathrm{n}\mathrm{m}}^2/\mathrm{s}$, $L_{f1}=22\mathrm{n}\mathrm{m}$, $D_{f2}=8.3\times {10}^3{\mathrm{n}\mathrm{m}}^2/\mathrm{s}$, $L_{f2}=25\mathrm{n}\mathrm{m}$. (f) Intra-chain (cyan) and inter-chain (dark blue) hole mobilities obtained from early time MSD fitting versus 0–0/0–1 peak ratio of the local spectra.