Fig. 3. Temperature-dependent transport properties of GaN and SnSe.

a Comparison of the electron mobility, μ, of GaN against experiment (black triangles,⁹²). Mobility limited by ionized impurity (teal, ii), acoustic deformation potential (orange, ad), and polar optical phonon scattering (pink, po) is indicated in dashed lines. Total mobility taking into account all scattering mechanisms ($1/{\tau }_{n\mathbf{k}}^{\mathrm{ii}}+1/{\tau }_{n\mathbf{k}}^{\mathrm{ad}}+1/{\tau }_{n\mathbf{k}}^{\mathrm{po}}$) is given by the black solid line. Constant relaxation time (CRT) calculations with τ = 10 fs is given by dotted gray line. b Electron lifetimes, τ_nk and (c) spectral conductivity, Σ, arising from different scattering processes in GaN at 300 K. The valence band maximum is set to zero eV. In (b), the vertical dotted gray line indicates the energy of the effective polar phonon frequency, ω_po. d Comparison of the direction-dependent mobility of SnSe against experiments—a (orange), b (teal), c (pink) points from ref. ⁶⁶, b–c (black) points from ref. ⁹³.