Fig. 4: Power dependence of exciton transport properties.

Evolution of the effective diffusion length (L_eff) with the excitation power density measured in WSe₂. Results obtained from time revolved PL profiles (see supplementary information). Error bars are mainly due to the fitting errors (linear fitting of the squared width, and bi-exponential fitting for τ (see supplementary information)). The inset shows the power dependence of the effective diffusion coefficient (D_eff).