  Semiconductor quantum dots (QDs) offer a platform to explore the physics of
quantum electronics including spins. Electron spins in QDs are considered good
candidates for quantum bits in quantum information processing, and spin control
and readout have been established down to a single electron level. We use these
techniques to explore spin dynamics in a hybrid system, namely a QD coupled to
a two dimensional electronic reservoir. The proximity of the lead results in
relaxation dynamics of both charge and spin, the mechanism of which is revealed
by comparing the charge and spin signal. For example, higher order charge
tunneling events can be monitored by observing the spin. We expect these
results to stimulate further exploration of spin dynamics in QD-lead hybrid
systems and expand the possibilities for controlled spin manipulations.
