Ultrafast relaxation dynamics of electronic excitations in noble-metal clusters

摘要: We investigate non-equilibrium relaxation processes in optically excited large gold and silver clusters. Time-resolved pump-probe experiments model calculations show that optical excitation of the clusters by femtosecond laser pulses results a heating electron system, which is followed cooling via phonon emission. The leads to an enhanced damping surface-plasmon resonance This caused enhancement Landau scattering rates at high temperatures. Furthermore, we find rate changes with temperature; this consequence temperature-dependent specific heat conduction electrons. Finally, on ellipsoidal thermal expansion heated triggers mechanical vibrations acoustic eigenfrequencies