on GaAs‐GaAlAs heterostructures. Magnetoresistance oscillations were used to investigate
the influence of an applied gate voltage on the 1D subband energies for various geometrical
widths of the fabricated quantum wires. For the first time, we measure directly the 1D
subband energies by tunneling spectroscopy. As a result, both the confining potential and
the influence of an additional magnetic field are well described by a simple harmonic …