Aharonov-Bohm effect in the Coulomb-blockade regime

The phase coherency in the current through a strongly correlated quantum dot is studied theoretically by calculating the amplitude and phase of the coherent transmission coefficient through a single level in the dot. The result is compared with the recent experiment in a four-terminal Aharonov-Bohm (AB) configuration. Another definition of the phase coherency, which is proportional to the transmission probability calculated from the coherent transmission coefficient, is introduced and shown to be different in magnitude from the one calculated from the AB conductance oscillations at temperatures much higher than the level broadening. (C) 1998 Elsevier Science Ltd. All rights reserved.