Electric conductance through a narrow constriction of width comparable to the electronic wavelength is quantized in units of 2e2/h, but a shoulder at around 0.7 of the conductance quantum is often present in measurements; detailed experiments now confirm that this effect is due to the emergence of localized states that result from many-body interactions between electrons in the constriction.
- M. J. Iqbal
- Roi Levy
- C. H. van der Wal
