Quantized conductance as a function of the charge carrier energy in modulat
ed quantum wires is investigated for the first time. The energy dependence
of the coefficient of transit through a modulated quantum wire was calculat
ed, with the delta-potential approximation used to describe the charge carr
ier quantum interference in the system of ultrasteep internal barriers. The
current steps and oscillations in the quantized conductance plateaus, obse
rvable as the oscillating features in the quantum wire conductance under va
rying longitudinal voltage, are predicted. Such oscillations, resulting fro
m the quantum interference of the ballistic holes, are observed experimenta
lly for the first time by recording quantized conductance plateaus as a fun
ction of the voltage applied along the silicon modulated quantum wire. (C)
2000 MAIK "Nauka/Interperiodica".