Characteristic Potentials for Mesoscopic Rings Threaded by an Aharonov-Bohm Flux

• Main Author: Buttiker, M.
• Format: Text
• Language: unknown
• Published: arXiv 1994
• Subjects: Condensed Matter cond-mat; FOS Physical sciences; Iceland
• Online Access: https://dx.doi.org/10.48550/arxiv.cond-mat/9407044; https://arxiv.org/abs/cond-mat/9407044

Electro-static potentials for samples with the topology of a ring and penetrated by an Aharonov-Bohm flux are discussed. The sensitivity of the electron-density distribution to small variations in the flux generates an effective electro-static potential which is itself a periodic function of flux. We investigate a simple model in which the flux sensitive potential leads to a persistent current which is enhanced compared to that of a loop of non-interacting electrons. For sample geometries with contacts the sensitivity of the electro-static potential to flux leads to a flux-induced capacitance. This capacitance gives the variation in charge due to an increment in flux. The flux-induced capacitance is contrasted with the electro-chemical capacitance which gives the variation in charge due to an increment in an electro-chemical potential. The discussion is formulated in terms of characteristic functions which give the variation of the electro-static potential in the interior of the conductor due to an increment in the external control parameters (flux, electro-chemical potentials). Paper submitted to the 16th Nordic Semiconductor Meeting, Laugarvatan, Iceland, June 12-15, 1994. The proceedings will be published in Physica Scripta. : 23 pages + 4 figures, revtex, IBM-RC19557