  In semiconductor-based quantum technologies, the capability to shuttle
charges between components is profoundly enabling. We numerically simulated
various "conveyor-belt" shuttling scenarios for simple Si/SiO2 devices,
explicitly modelling the electron's wave function using grid-based
split-operator methods and a time-dependent 2D potential (obtained from a
Poisson solver). This allowed us to fully characterise the electron loss
probability and excitation fraction. Remarkably, with as few as three
independent electrodes the process can remain near-perfectly adiabatic even in
the presence of pulse imperfection, nearby charge defects, and Johnson-Nyquist
noise. Only a substantial density of charge defects, or defects at
'adversarial' locations, can catastrophically disrupt the charge shuttling.
While we do not explicitly model the spin or valley degrees of freedom, our
results from this charge propagation study support the conclusion that
conveyor-belt shuttling is an excellent candidate for providing connectivity in
semiconductor quantum devices.
