Fig. 4: Electron-phonon scattering.
From: Ultrafast hot-carrier dynamics in ultrathin monocrystalline gold
a Measured normalised transient reflection from a 10-nm-thick MC Au MF (violet curve) and a PC Au film (green curve) on a SiO2 substrate, and a MC Au MF on a TiO2 substrate (red curve) at the excitation fluence F = 5.7 Jm−2. b Measured dependence of τe−ph of a 10-nm-thick MC Au MF on SiO2 (violet diamonds), on TiO2 (red squares), and a PC Au film on SiO2 (green dots) on the excitation fluence. The dotted curves are simulated with Eq. (2) for G\({}_{MCAu/Ti{O}_{2}}\) = 1.6 x 1016 Wm−3K−1 (red), G\({}_{PCAu/Si{O}_{2}}\) = 2 x 1016 Wm−3K−1 (green), and G\({}_{MCAu/Si{O}_{2}}\) = 2.2x1016 Wm−3K−1 (purple). Inset shows the comparison of the fluence dependence of τe−ph of a 10-nm-thick MC Au MF on TiO2 with the simulations for different values of Pi. c Thickness dependence of measured τe−ph for MC Au MFs on SiO2 in strong (dots), and weak (diamonds) perturbation regimes. Solid curves are the calculated electron temperatures Te achieved in strong (upper) and weak (lower) perturbation regimes. Error bars in (b, c) represent standard deviation.
