Crossover from weak localization to anti-weak localization in indium oxide systems with wide range of resistivity

We investigated the magnetoconductivity Δσ(H)≡1/ρ(H)−1/ρ(0) in a wide range of magnetic fields for three-dimensional indium oxide films doped with zinc, tin, or gallium in the range of resistivity ρ(300K) between 4.1×10−6 Ωm and 1.7×10−3 Ωm. The weak localization theory was fitted to data for Δσ(H) at various temperatures in the range 2.0 K≤T≤50 K by the use of suitable characteristics Dτin(T) and Dτso, where D, τin, and τso are the electron diffusion constant, inelastic scattering time, and spin-orbit (s-o) scattering time, respectively. It was found that (i) for films with a large value of ρ, the sign of Δσ(H) changes from positive to negative with decreasing temperature as a precursor to an anti-weak localization effect; (ii) the ratio τso/τin decreases from ≈4000 to≈4.0 with increasing ρ; (iii) the strong ρ dependence of Dτso cannot be explained by the model with a constant atomic number Z in a formula τso∝1/Z4 proposed by Abrikozov and Gorkov Zh. Eksp. Teor. Fiz. 42, 1088 (1962); [Sov. Phys. JETP 15,...