Indirect exchange coupling between two nuclei of magnetic impurities in 2DES: Strong scattering limitP. Dahan
School of Engineering at Ruppin Academic Center - Emek-Hefer 40250, Israel
received 8 February 2006; accepted in final form 24 May 2006
published online 14 June 2006
The indirect exchange interaction between two magnetic impurities in a two-dimensional electron system under strong magnetic field is studied. The nuclear spin coupling is mediated by Landau electrons bound to these impurities. The d-electrons are indirectly involved in the contact interaction through their resonance scattering potential with the bound Landau electrons. The obtained superexchange interaction between two different sites results in an antiferromagnetic interaction between the nuclear spins of the impurities. The coupling constant between these nuclear spins, J, is found to be strongly dependent on the ratio of the impurity separation over the magnetic length. Possible applications of these results include a long-range mechanism for coupling between two nuclear spins to be used as a qubits interaction with a spacing distance of the order of the magnetic length.
75.30.Et - Exchange and superexchange interactions.
71.55.-i - Impurity and defect levels.
73.21.-b - Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems.
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