  We demonstrate delicate control over the Kondo effect and its interplay with
quantum interference in an Aharonov-Bohm interferometer containing one Kondo
dot and one noninteracting dot. It is shown that the Kondo resonance undergoes
a dramatic evolution as the interdot tunnel coupling progressively increases. A
novel triple Kondo splitting occurs from the interference between constant and
Lorentzian conduction bands that cooperate in forming the Kondo singlet. The
device also manifests a highly controllable Fano-Kondo effect in coherent
electronic transport, and can be tuned to a regime where the coupled dots
behave as decoupled dots.
