I work on electron transport in nanoscopic systems, in particular on the far non-equilibrium transient currents through molecular bridges linking bulk metal electrodes. The field is reviewed in [1], with emphasis on the widely accepted field-theoretical methods (non-equilibrium Green’s functions) and their systematic simplification to quantum transport equations, which is important both fundamentally and practically – for computations. The universal approximate path to the quantum transport equations is based on the generalized Kadanoff–Baym ansatz. It works well for normal metal electrodes, but fails for tunneling between ferromagnetic electrodes. A breakthrough was achieved by supplementing the ansatz by asymptotic vertex corrections [2],[3].
[1] V. Špička, B. Velický, A. Kalvová, Non-equilibrium dynamics of open systems and fluctuation-dissipation theorems, Fortschr. Phys. 65, 1700032 (2017);
[2] A. Kalvová, B. Velický, V. Špička, Generalized master equation for molecular bridge improved by vertex correction to the Generalized Kadanoff Baym Ansatz, EPL 121, 67002 (2018);
[3] A. Kalvová, B. Velický, V. Špička, Beyond the Generalized Kadanoff-Baym Ansatz, Phys. Status Solidi B 256 1800594 (2019).
