FIG.107 Inset: Corrugated gate used

FIG.107 Inset: Corrugated gate used to define a narrow channel with a one-dimensional periodic potential (the total number of barriers is 16, corresponding to 15 unit cells). Plotted is the conductance in a magnetic field of 2 T as a function of the voltage on the smooth gate at 10 mK. The deep conductance minima (marked by + and ∗) are attributed to minigaps, and the 15 enclosed maxima to discrete states in the miniband. Taken from L. P. Kouwenhoven et al., Phys. Rev. Lett. 65, 361 (1990). FIG.108 Top: Calculated transmission probability TN of an edge channel through a periodic potential of N = 15 periods as a function of the Aharonov-Bohm phase eBS/¯h (with S the area of one unit cell). The transmission probability through a single barrier is varied as shown in the bottom panel. Taken from L. P. Kouwenhoven et al., Phys. Rev. Lett. 65, 361 (1990). FIG.109 Illustration of magnetically induced band structure in a narrow channel with a weak periodic modulation of the confining potential V (x) (for the case V (x) 6= V (−x)). The dashed curves represent the unperturbed dispersion relation (4.49) for a single Landau level. Skew minibands result from the broken time-reversal symmetry in a magnetic field.