Influence of the electrodynamic environment on quantum adiabatic transport

The quantum ballistic transport of electrons through a constriction in a 2-dimensional electron gas is characterized by a conductance quantized in units of e2/h. We study the effect of transport- and gate-voltage fluctuations on this quantization. They give rise to transitions between the adiabatic transport channels. Intrachannel scattering is stronger than interchannel scattering and transport voltage fluctuations contribute more than those of the gate voltage. The effect of transport voltage fluctuations is characterized by a universal low-frequency behaviour