  We investigate low-temperature transport characteristics of a side-coupled
double quantum dot where only one of the dots is directly connected to the
leads. We observe Fano resonances, which arise from interference between
discrete levels in one dot and the Kondo effect, or cotunneling in general, in
the other dot, playing the role of a continuum. The Kondo resonance is
partially suppressed by destructive Fano interference, reflecting novel
Fano-Kondo competition. We also present a theoretical calculation based on the
tight-binding model with slave boson mean field approximation, which
qualitatively reproduces the experimental findings.
