Numerical calculations of variable-range hopping in one-dimensional MOSFETs

The conductivity sigma for electron transport via strongly localised electron states in a one-dimensional MOSFET has been determined by the direct solution of the Miller-Abrahams equivalent network equations (1960). Random fluctuations of log sigma proportional to T -1/2 are observed as the chemical potential mu moves through an energy band of width W. The fluctuations are smaller than those determined recently by Lee (1984) using a percolation argument and the proportionality constant is 60% higher. As the temperature decreases the fluctuations increase from approximately one order of magnitude when kT/W=0.008 to approximately nine orders of magnitude when kT/W=0.001. The conductivity decreases to an asymptotic limit as the length of the system increases.