  We theoretically investigate the electronic transport properties of curved
graphene waveguides by employing non-equilibrium Green's function techniques.
We systematically study the dependence of the confined waveguide modes on the
potential difference, the width of waveguide and side barrier. Through
two-terminal electronic transport calculations, we show that the conductance of
confined waveguide modes is rather robust against the bending degree of
waveguide, in consistent with the band insensitivity to the side barrier. This
finding of the perfectly conducting channels strongly suggests the possibility
of applying the graphene waveguide in the design of low-power nanoelectronics.
