Non-equilibrium electrons in a ballistic quantum dot

An experimental study of a ballistic quantum dot that is not in thermal equilibrium is presented. The resistance of the dot is found to strongly decrease as a function of the bias voltage that is used to inject non-equilibrium electrons into the dot. An estimate of the voltage induced electron temperature in the dot shows that this behaviour is due to both current heating and non-equilibrium effects. In particular, weak localization in the dot is suppressed by phase breaking due to electron-electron (e-e) interaction of the non-equilibrium probe electrons. A model that accounts for this effect is presented.