Quantum Interference Effects, Magnetoresistance and Localisation in Disordered Systems
نویسنده
چکیده
The magnetoresistivity of a disordered metallic system is derived using the a2KF-scatteringo theory in terms of a generalized Boltzmann equation with magnetic field B included. The behaviour is complex but in the limit of weak fields (which are experimentally quite strong) we find a negative contribution to the relaxation time proportional to B which gives rise to a positive magnetoconductivity proportional to B: The conductivity in zero field increases with temperature. We discuss these results in the context of measurements for amorphous CazAl1ÿ z and existing theories of magnetoconductivity. The theory explains the nature of the observed results. It can also be generalised to strong localisation and applied in strong scattering situations.
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