Conductance oscillations in mesoscopic rings: microscopic versus macroscopic picture

摘要

The phase of Aharonov-Bohm oscillations in mesoscopic metal rings in thepresence of a magnetic field can be modulated by application of a DC-biascurrent I_DC. We address the question of how a variation of I_DC and hence ofthe microscopic phases of the electronic wave functions results in themacroscopic phase of the conductance oscillations. Whereas the first one can bevaried continuously the latter has to be quantized for a ring in two-wireconfiguration by virtue of the Onsager symmetry relations. We observe acorrelation between a phase flip by +/- pi and the amplitude of theoscillations.