The electron-phonon relaxation time in thin superconducting titanium nitride films

We report on the direct measurement of the electron-phonon relaxation time, {tau}eph, in disordered TiN films. Measured values of {tau}eph are from 5.5 ns to 88 ns in the 4.2 to 1.7 K temperature range and consistent with a T-3 temperature dependence. The electronic density of states at the Fermi level N0 is estimated from measured material parameters. The presented results confirm that thin TiN films are promising candidate-materials for ultrasensitive superconducting detectors.