2011/03/12 by A. U. Sharafutdinov, I. S. Burmistrov
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1088/0953-8984/24/15/155301
published as J. Phys.: Condens. Matter 24, 155301 (2012) · LaTex, 14 pages
arxiv created 2011/03/12 · openalex publication_date 2012/03/22 · arxiv updated 2012/04/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The cotunneling current through a two-level quantum dot weakly coupled to ferromagnetic leads is studied in the Coulomb blockade regime. The cotunneling current is calculated analytically under simple but realistic assumptions as follows: (i) the quantum dot is described by the universal Hamiltonian, (ii) it is doubly occupied, and (iii) it displays a fast spin relaxation. We find that the dependence of the differential conductance on the bias voltage is significantly affected by the exchange interaction on the quantum dot. In particular, for antiparallel magnetic configurations in the leads, the exchange interaction results in the appearance of interference-type contributions from the inelastic processes to the cotunneling current. Such dependence of the cotunneling current on the tunneling amplitude phases should also occur in multi-level quantum dots weakly coupled to ferromagnetic leads near the mesoscopic Stoner instabilities.