K. Kohary et al., One-dimensional hopping transport in disordered organic solids. II. Monte Carlo simulations - art. no. 094202, PHYS REV B, 6309(9), 2001, pp. 4202
Drift mobility of charge carriers in strongly anisotropic disordered organi
c media is studied by Monte Carlo computer simulations. Results for the nea
rest-neighbor hopping are in excellent agreement with those of the analytic
theory (Cordes et al., preceding paper). It is widely believed that the lo
w-field drift mobility in disordered organic solids has the form mu infinit
y exp[-(T-0/T)(2)] with characteristic temperature T-0 depending solely on
the scale of the energy distribution of localized states responsible for tr
ansport. Taking into account electron transitions to more distant sites tha
n the nearest neighbors, we show that this dependence is not universal and
parameter T-0 depends also on the concentration of localized states and on
the decay length of the electron wave function in localized states. The res
ults of computer simulation evidence that correlations in the distribution
of localized states influence essentially not only the held dependence as k
nown from the literature, but also the temperature dependence of the drift
mobility. In particular, strong space-energy correlations diminish the role
of long-range hopping transitions in the charge carrier transport.