TUNNELING THROUGH A BARRIER IN A TOMONAGA-LUTTINGER LIQUID CONNECTED TO RESERVOIRS

The transport through a barrier is studied for a Tomonaga-Luttinger li quid of finite length connected to reservoirs. An effective action for the phase variable at the barrier is derived for spatially varying el ectric field. In the dc limit only the total voltage drop between the left and right reservoirs appears in the action. We discuss crossovers of the renormalization group flow and hence of the temperature and wi re length dependence of the conductance, taking into account the locat ion of the barrier.