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author = {Noat, Y., Deblock, R., Reulet, B., Bouchiat, H.},
title = {Magnetopolarizability of mesoscopic systems},
journal = {Physical Review B - Condensed Matter and Materials Physics},
year = {2002},
volume = {65},
number = {7},
pages = {0753051-07530512},
art_number = {075305},
note = {cited By (since 1996) 0},
url = {http://www.scopus.com/inward/record.url?eid = 2-s2.0-0037084632&partnerID = 40&md5 = 595c17c92731ddbc74355030a97d988e},
affiliation = {Laboratoire de Physique des Solides, Associé au CNRS, Université Paris-Sud, 91405 Orsay, France},
abstract = {In order to understand how screening is modified by electronic interferences in a mesoscopic isolated system, we have computed both analytically and numerically the average thermodynamic and time-dependent polarizabilities of two-dimensional mesoscopic samples in the presence of an Aharonov-Bohm flux. Two geometries have been considered: rings and squares. Mesoscopic correction to screening are taken into account in a self consistent way, using the response function formalism. The role of the statistical ensemble (canonical and grand canonical), disorder and frequency have been investigated. We have also computed first order corrections to the polarizability due to electron-electron interactions. Our main results concern the diffusive regime. In the canonical ensemble, there is no flux dependence in the polarizability when the frequency is much smaller than the level spacing. On the other hand, in the grand canonical ensemble for frequencies larger than the mean broadening of the energy levels (but still small compared to the level spacing), the polarizability oscillates with flux, with the periodicity h/2e. The order of magnitude of the effect is given by δα/α∝(λs/Wg), where λ is the Thomas-Fermi screening length, W the width of the rings or the size of the squares, and g their average dimensionless conductance. This magnetopolarizability of Aharonov-Bohm rings has been recently measured experimentally [R. Deblock, Y. Noat, H. Bouchiat, B. Reulet and D. Mailly, Phys. Rev. Lett. 84, 3579 (2000)] and is in good agreement with our grand canonical result.},
document_type = {Article},
source = {Scopus}}