Effect of inhomogeneous magnetic flux on double-dot Aharonov-Bohm interferometer

The influence of the inhomogeneous distribution of the magnetic flux on quantum transport through coupled double quantum dots embedded in an Aharonov-Bohm interferometer are investigated. We show that the effective tunnelling coupling between two dots can be tuned by the magnetic flux imbalance threading two AB subrings. Thus the conductance and the local densities of states become periodic functions of the magnetic flux imbalance. Therefore, transport signals can be manipulated by adjusting the magnetic flux imbalance. Thus accurate control of the distribution of the magnetic flux is necessary for any practical application of such an Aharonov-Bohm interferometer.