Electron-phonon relaxation dynamics of niobium metal as a function of temperature

Abstract
The electron-phonon relaxation process in niobium has been measured with pump-probe technique and compared with theory for ambient (initial) temperatures ranging from 292 to 7 K. The time it takes for the electrons to thermalize with phonons was found to decrease from 370 fs at 292 K to 250 fs at 7 K, while the electron-phonon coupling parameter g decreases with decreasing temperature.