Electron-phonon coupling and hot electron thermalization in titanium nitride

Abstract

We have studied the thermalization of hot carriers in both pristine and defective titanium nitride (TiN) using a two-temperature model. All parameters of this model, including the electron-phonon coupling parameter, were obtained from rst-principles density-functional theory calculations. The virtual crystal approximation was used to describe defective systems. We nd that thermalization of hot carriers occurs on much faster time scales than in gold as a consequence of the signi cantly stronger electronphonon coupling in TiN. Speci cally, the largest thermalization times, on the order of 200 femtoseconds, are found in TiN with nitrogen vacancies for electron temperatures around 4000 K.