2008/06/05 by Oleksandr Zelyak, Ganpathy Murthy
Physics and Astronomy · #Classical mechanics #Condensed matter physics #Current (fluid) #Diamagnetism #Dynamical billiards #Electron #Flux (metallurgy) #Gyroradius #Magnetic field #Magnetic flux #Mesoscopic physics #Nuclear physics research studies #Persistent current #Physics #Quantum #Quantum chaos and dynamical systems #Quantum electrodynamics #Quantum mechanics #Quantum, superfluid, helium dynamics #Semiclassical physics #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.78.125305
20 pages, 11 figures; added references for section 1
arxiv created 2008/06/05 · openalex publication_date 2008/09/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the persistent current of noninteracting electrons subject to a pointlike magnetic flux in the simply connected chaotic Robnik-Berry quantum billiard and also in an annular analog thereof. For the simply connected billiard, we find a large diamagnetic contribution to the persistent current at small flux, which is independent of the flux and is proportional to the number of electrons (or equivalently the density since we keep the area fixed). The size of this diamagnetic contribution is much larger than mesoscopic fluctuations in the persistent current in the simply connected billiard. Moreover, it can ultimately be traced to the response of the angular-momentum l=0 levels (neglected in semiclassical expansions) on the unit disk to a pointlike flux at its center. The same behavior is observed for the annular billiard when the inner radius is much smaller than the outer one. The usual fluctuating persistent current and Anderson-like localization due to boundary scattering are seen when the annulus tends to a one-dimensional ring. We explore the conditions for the observability of this phenomenon.