We investigate charge transport through electronic surface states of the $6H\text{‐}\mathrm{Si}\mathrm{C}\left(0001\right)\text{‐}3\times 3$ surface. Three intrinsic surface states are located within the wide bulk band gap, in which two ($S_1$ and $U_1$) arise from strongly correlated electronic states and the third $\left(S_2\right)$ has negligible electron correlation effects. Combined conductance and luminescence experiments with the scanning tunneling microscope show that the Mott-Hubbard surface states ($S_1$ and $U_1$) have a high resistance $\left(1.0\mathrm{G}\Omega \right)$, while the noncorrelated state $\left(S_2\right)$ has a negligible resistance. Consequently, current can be selectively transported through any of these three surface states.

• Received 11 February 2008

DOI:https://doi.org/10.1103/PhysRevB.77.165320