We present Nb/AlOx/Nb-Al/AlOx/Nb stacked Josephson junctions which we propo
se as three-terminal elements to control the quantum behavior of Josephson
complex systems. A bias current can be independently injected in the "top"
junction, providing a fine control of the critical current of the "bottom"
junction. The reported characterization of the device refers to data in the
classical limit including measurements of the switching dynamics between m
etastable states of the system at different temperatures and bias condition
s. At low temperature, the effective dissipation of the bottom junction rem
ains substantially unchanged when different injection currents flow in the
top junction. These results are interesting to project new configurations o
f macroscopic quantum experiments. (C) 2001 American Institute of Physics.