  The transient processes of electron transport in nano-scale devices exhibit
special phenomena that exist only in the transient regime. Besides how fast the
steady states are approached, one interesting aspect of transient transport
arises from its strong dependence on the initial state of the system. Here we
address the issue of how the symmetries embedded in the initial state interplay
with those of the system structure in the course of transient transports. We
explicitly explore the transient currents arising from various initial
occupations in a double-quantum-dot Aharonov-Bohm interferometer. We find
symmetry relations between the transient in-tunneling and out-tunneling
dynamics for initially empty or full quantum dots when the energy levels in the
electrodes are symmetrically distributed with respect to the energy levels in
the QDs. This is true for whatever applied fluxes. We also find the flux-even
components of the currents and the flux-odd components of the currents exhibit
distinct cross-lead symmetric relations.
