Metal‐insulator transition in Bi‐doped, amorphous Ga:Ar mixtures: Influence of spin‐orbit scattering

Doping amorphous Ga x Ar 1−x mixtures with the strong spin‐orbit scatterer Bi has a dramatic effect on the metal‐insulator transition (MIT) occurring in this system at a critical metal atomic concentration x c : (i) the MIT is shifted from x ′ c = 0.36 ± 0.01 (corresponding to a critical metal volume fraction v ′ c = 0.19 ± 0.01) of the undoped system to a lower value of x c = 0.25 ± 0.01 ( v c = 0.14 ± 0.01) for (Ga 0.9 Bi 0.1 ) x Ar 1−x and (ii) the critical exponent v and g of the dc conductivity and Hall coefficient, respectively, change from v ′ = 0.5 ± 0.1 and g ′ = 0 for the undoped samples to v = 1.3 ± 0.3 and g = 0.5 ± 0.1 for (Ga 0.9 Bi 0.1 ) x Ar 1−x .