A comment on the Kawabata theory of magnetoresistance in disordered systems

Influence of spin–orbit interaction on the electrical conductivity of three‐dimensional disordered systems

“…To explain the experimental results the authors of the quoted papers used to apply the theory of Fukuyama and Hoshino [16] which was an extension of a previous theory of Kawabata [17,18] developed for the magnetoconductivity of disordered systems. However we have argued [19] that Kawabata's theory, originally formulated for degenerate semiconductors, is of uncertain validity for amorphous metals, where very often the Ioffe-Regel criterion is not valid [20] or one is working at the limit of its validity. In the discussion of electron transport properties we will consider nearly free electrons moving in a disordered system of weak potentials and neglect electron-electron scattering effects and internal fields arising from the electron-electron interaction.…”

“…The motivation for this work is that we have some reservations about existing treatments [19] but we are building on the previous ideas of others in this paper and are seeking to establish the relationship between this and previous work.…”

Transition from positive to negative magnetoresistance induced by a constriction in semiconductor nanowire

“…In the disordered systems it can be explained by the weak localization theory, which predicts the negative MR with the √ B-dependence. [11][12][13] Moreover, in the disordered systems, the sign of MR can be affected by the spin-orbit interaction. [14][15][16][17] Nevertheless, in organic semiconductor devices the transition between positive and negative MR due to the applied voltage and temperature has been observed, 18,19 but the microscopic origin of this effect is still unclear.…”