Conductance Oscillations Periodic in the Density of a One-Dimensional Electron Gas

By use of x-ray lithography Si inversion layers have been fabricated with width ∼25 nm and mobility ∼15 000 ${\mathrm{cm}}^2$/V s. These display oscillations in their conductance that are periodic in the number of electrons per unit length, even in zero magnetic field. The oscillations reflect an oscillatory activation energy of the conductance and are accompanied by unusual nonlinearities suggestive of pinned charge-density waves.