Figure 3
Initial dynamics induced by the pump pulse.
(a) Spectra recorded at T = 10 K, p = 29 µJ/cm2 and τ = 4 µs at several delays. The averaged spectrum before -0.33 ps is also overlaid on each spectrum. The shift of the spectra into the unoccupied side becomes prominent at 
, which is attributed to the variation of the surface photovoltage induced by the pump pulse. (b, c) Spectra in a logarithmic scale plot at T = 10 and 130 K, respectively. The energy scale of 4kBT is also displayed. (d) Pump-induced difference of the spectrum (upper panels) and excess-energy distributions (lower panels) mapped in the ω - t plane (ω ≡ E − EF) at various temperatures. (e) Dissipation of the excess-electronic energy (see, text) at various temperatures.
