Ai. Yakimov et al., Oscillations of hopping conductance in an array of charge-tunable self-assembled quantum dots, J PHYS-COND, 11(48), 1999, pp. 9715-9722
An array of 3 x 10(7) Ge self-assembled quantum dots is embedded into the a
ctive channel of a Si metal-oxide field-effect transistor. Conductance osci
llations with the gate voltage resulting from successive loading of holes i
nto the dots are observed. On the basis of measurements of the temperature
dependence of the conductance maxima, the charge-transfer mechanism in the
channel is identified as being due to variable-range hopping between the do
ts, with the typical hopping energy determined by inter-dot Coulomb interac
tion. The characteristic spatial dimension of the hole wavefunctions as wel
l as the charging energies of the dots are determined from the conductance
data.