Analysis of the temperature - dependent quantum point contact conductance in view of the metal - insulator transition in two dimensions

Analysis of the temperature-dependent quantum point contact conductance in view of the metal-insulator transition in two dimensions Abstract The temperature dependence of the conductance of a quantum point contact has been measured. The conductance as a function of the Fermi energy shows temperature-independent fixed points, located at roughly multiple integers of e 2 /h. Around the first fixed point at e 2 /h, the experimental data for different temperatures can been scaled onto a single curve. For pure thermal smearing of the conductance steps, a scaling parameter of one is expected. The measured scaling parameter, however, is significantly larger than 1. The deviations are interpreted as a signature of the potential landscape of the