Abstract
Extending a random-matrix theory developed earlier, we show that breaking a basic symmetry in an Anderson insulator (e.g., time-reversal symmetry or spin-rotation symmetry) generically yields a multiplication of the localization length ξ by universal factors. Numerical calculations and magnetoconductance measurements in the Mott variable-range-hopping regime confirm that the removal of time-reversal symmetry by a magnetic field yields ξ→2ξ in the absence of spin-orbit scattering, and ξ→ξ/2 in the presence of spin-orbit coupling.
- Received 29 May 1990
DOI:https://doi.org/10.1103/PhysRevLett.65.1812
©1990 American Physical Society