Dresden 2006 – wissenschaftliches Programm

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TT: Tiefe Temperaturen

TT 20: Transport: Nanoelectronics I - Quantum Dots, Wires, Point Contacts - Part 2

TT 20.6: Vortrag

Dienstag, 28. März 2006, 15:30–15:45, HSZ 105

Fano interference and Kondo correlations in the non-linear regime of simple mesoscopic models. — •Alexandru Aldea, Viorel Dinu, and Mugurel Tolea — National Institute of Materials Physics, Bucharest-Magurele, Romania

The Fano effect in mesoscopic systems consists in the asymmetric shape of electron transmittance peaks due to the interference of electron waves propagating along channels with strongly different properties. The tunneling process is additionally affected by the Kondo-type correlation between the spin of the dot and the spin of the incoming electron. The consequences of correlations can be noticed in the local density of states and in changes of the shape of Fano lines. This effect is known as the Fano-Kondo effect and combines the main ingredients of meso-systems: the geometry and interaction . In this work we analyze simple models like the T-shape and triangle model in order to identify specific contributions of the interaction and geometry for the transport properties in the linear and non-linear regime; the triangle model allows also for the magnetic field effects. We calculate the local DoS and conductance in a large range of relevant parameters by the use of the tight-binding Hamiltonian description [1] and non-equilibrium Green function formalism. The equation of motion method is used along with [2].

[1] V.Moldoveanu, M.Tolea, A.Aldea, and B.Tanatar, Phys. Rev. B 71, 125338 (2005).

[2] O.Entin-Wohlman et al, Phys. Rev. B 71, 035333 (2005).