AHARONOV-BOHM EFFECT IN THE PRESENCE OF MAGNETIC-FLUX AND ELECTROSTATIC POTENTIAL

We present a calculation of Aharonov-Bohm (AB-effect) conductance oscillations in a mesoscopic ring in the presence of both magnetic flux and electrostatic potential. Their combination exhibits some new aspects of conductance oscillations. Conductance oscillations with a period of 2pi shift their phase by pi as a function of the electrostatic potential (or magnetic flux) when the magnetic flux (or electrostatic potential) changes. We derive the phase shift relations for distinct AB interference by which these oscillations are fully understood. A full taxonomy of the rich varieties of interference modes is established and confirmed by numerical calculations. In some conditions, conductance oscillations with periods of half the flux quantum h/2e and full swing amplitudes of e2/h are predicted in both electrostatic and magnetostatic AB effects. The influence of diffuse scattering on the electrostatic AB effect is also examined.