  The physics of a junction composed of a normal metal, quantum dot and 2D
topological insulator (in a quantum spin Hall state) is elucidated. It maifests
a subtle combination of Kondo correlations and quantum spin Hall edge states
moving on the opposite sides of the 2D topological insulator. In a narrow strip
geometry these edge states interact and a gap opens in the edge state spectrum.
Consequently, Kondo screening is less effective and that affects electron
transport through the junction. Specifically, when edge state coupling is
strong enough, the tunneling differential conductance develops a dip at zero
temperature instead of the standard zero bias Kondo peak.
