A. Gupta, R. Gross, et al.
SPIE Advances in Semiconductors and Superconductors 1990
The magnetic field dependence (H<15 T) and the temperature dependence (380 mK<T<30 K) of hopping conduction have been measured in a quasi-two-dimensional impurity band formed in the inversion layer of a sodium-doped silicon metal-oxide-semiconductor field-effect. We find that the positive magnetoresistance observed in the weak-field regime is consistent with the prediction of Shklovskii, i.e., ln[σ(H,T)/σ(0,T)]=-Cξc03 /(λα)4, where the conductivity at the percolation threshold in the absence of a field is σ(0,T)=σ0exp(-ξc0), the exponent ξc0 is determined from a noninteracting single-particle hopping model, λ=(ch/eH)1/2, α is the exponential decay rate of the localized state, and C is a positive constant. This work represents the first comprehensive evaluation of Shklovskii's percolation model for hopping magnetoresistance. © 1986 The American Physical Society.
A. Gupta, R. Gross, et al.
SPIE Advances in Semiconductors and Superconductors 1990
A. Reisman, M. Berkenblit, et al.
JES
S.F. Fan, W.B. Yun, et al.
Proceedings of SPIE 1989
K.A. Chao
Physical Review B