Cb. Whan et al., FULL CAPACITANCE MATRIX OF COUPLED QUANTUM-DOT ARRAYS - STATIC AND DYNAMICAL EFFECTS, Applied physics letters, 68(21), 1996, pp. 2996-2998
We numerically calculated the full capacitance matrices for both one-d
imensional (1D) and two-dimensional (2D) quantum-dot arrays. We found
it is necessary to use the full capacitance matrix in modeling coupled
quantum dot arrays due to weaker screening in these systems in compar
ison with arrays of normal metal tunnel junctions. The static soliton
potential distributions in both 1D and 2D arrays are well approximated
by the unscreened (1/r) Coulomb potential, instead of the exponential
fall-off expected from the often used nearest neighbor approximation.
The Coulomb potential approximation also provides a simple expression
for the full inverse capacitance matrix of uniform quantum dot arrays
. In terms of dynamics, we compare the current-voltage (I-V) character
istics of voltage biased 1D arrays using either the full capacitance m
atrix or its nearest neighbor approximation. The I-V curves show clear
differences and the differences become more pronounced when larger ar
rays are considered. (C) 1996 American Institute of Physics.