Spin and Charge Current in a Short Semiconducting Chain of Paramagnetic Ionic Blocks |
| A. Lehmann-Szweykowska, R.J. Wojciechowski and R. Micnas
Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland |
| Full Text PDF |
| We deal with the electric current flowing through a short chain of paramagnetic ionic blocks, coupled to metallic electrodes in the serial configuration. An original three-band Hubbard-Anderson Hamiltonian is diagonalised at the level of the single ionic block. A minimal but sufficient set of the latter's four hybridised eigenstates serves as a basis for the determination of the time-ordered temperature-dependent matrix Green functions, in terms of which all the current-voltage (I-V) characteristics can be expressed provided the coupling to the electrodes is weak. The separation of the opposite-spin contributions to the electric current and, consequently, the spin current from the left to right electrode can result from the on-site Coulomb repulsion term of Hubbard-Anderson Hamiltonian, with no spin polarisation at the electrodes, but with the Zeeman-like coupling of the centre to either a molecular or an external magnetic field. |
| DOI: 10.12693/APhysPolA.115.260 PACS numbers: 72.25.Dc, 73.61.Le, 73.63.Rt |