Electron-electron interaction and weak-localization effects in Ti-Al alloys

We have measured the resistivities {ρ} of Ti_1-x{Al}ₓ$ alloys (0.00{≤}x{≤}0.19) between 4 and 300 K. As the temperature T is lowered to liquid-helium temperatures, a resistivity rise [{ρ}(T)-{ρ}(25 K)]/ {}T {~}-ρ2.5(25 K) is observed. This functional form is due to electron-electron interaction effects in a three-dimensional disordered metal. Particularly, the absolute magnitude of the measured resistivity rise is consistent within {~}25% with the theoretical prediction. At room temperature, the temperature coefficient of resistivity (1/{ρ})(d{ρ}/dT) decreases monotonically with increasing x or, equivalently, {ρ}. The essential characteristics of the variation of (1/{ρ})(d{ρ}/dT) with {ρ} is explained in terms of a theory that considers a competition between the quantum-mechanical effects of weak localization and the classical Boltzmann electron transport.