We find that strong magnetic fields reduce the effectiveness of the Coulomb gap in determining the variable-range-hopping (VRH) resistivity. We propose a crossover phenomenon characterized by a temperature Tc with the Coulomb gap affecting the VRH resistivity only below Tc. The value of Tc decreases as the magnetic field increases. Our theoretical model explains the observed crossover from a ln (H=0) T-1/2 law to a ln (H) [T0(H)/T]1/3 law with T0H.
|Number of pages||4|
|Journal||Physical Review Letters|
|State||Published - 1992|