Disorder Dependence of Electron-Phonon Scattering Time in Bulk Ti 1- x Al x Alloys

We have fabricated crystalline disordered bulk Ti 1- x Al x alloys (0.04 ≲ x ≲ 0.15) with impurity resistivities ρ(10 K) varying from ≈ 60 to 180 μΩ cm. With this wide range of ρ(10 K) controllably accessible, we were able to perform an experimental investigation of the disorder dependence of electron-phonon scattering time τ e-ph . We measured the magnetoresistivities of these alloys, and compared our measured results with weak-localization and Maki-Thompson superconducting fluctuation theories to extract τ e-ph . We found that τ e-ph in all alloys obey a T -2 -dependence in our temperature range of (3-10) K. Particularly, we observed that τ e-ph scales with disorder, i.e. τ e-ph ∼ ρ -1 for ρ(10 K) in the range (60-150) μΩ cm. Our results support a theory of electron-phonon interaction in disordered metals, which considers an Eliashberg function α 2 F (ω) that is linear in ω. The magnitudes of our measured τ e-ph are consistent within ∼ 40% with the theoretical prediction.