Abstract:Femtosecond pulses at wavelengths ranging from 750 to 900 nm (1.38–1.65 eV) were used in the excitation and probing of ultrafast carrier dynamics in InN epitaxial films. Experimental results show that the hot electron relaxation rate increases with increasing electron energy, which is measured as E0.53. This observation agrees with the prediction of electron-electron scattering relaxation mechanism. In addition, the electron-hole recombination rates are independent of the electron energy and have values of ∼ 7×109 Hz. We attribute this result to the Auger recombination in InN being insensitive to temperature.