A1 Journal article (refereed)
Electronic transport in molecular junctions : The generalized Kadanoff–Baym ansatz with initial contact and correlations (2021)

Tuovinen, R., van Leeuwen, R., Perfetto, E., & Stefanucci, G. (2021). Electronic transport in molecular junctions : The generalized Kadanoff–Baym ansatz with initial contact and correlations. Journal of Chemical Physics, 154(9), Article 094104. https://doi.org/10.1063/5.0040685

JYU authors or editors

Publication details

All authors or editors: Tuovinen, Riku; van Leeuwen, Robert; Perfetto, Enrico; Stefanucci, Gianluca

Journal or series: Journal of Chemical Physics

ISSN: 0021-9606

eISSN: 1089-7690

Publication year: 2021

Publication date: 07/03/2021

Volume: 154

Issue number: 9

Article number: 094104

Publisher: AIP Publishing

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1063/5.0040685

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/80376

Web address of parallel published publication (pre-print): https://arxiv.org/abs/2012.08247


The generalized Kadanoff–Baym ansatz (GKBA) offers a computationally inexpensive approach to simulate out-of-equilibrium quantum systems within the framework of nonequilibrium Green’s functions. For finite systems, the limitation of neglecting initial correlations in the conventional GKBA approach has recently been overcome [Karlsson et al., Phys. Rev. B 98, 115148 (2018)]. However, in the context of quantum transport, the contacted nature of the initial state, i.e., a junction connected to bulk leads, requires a further extension of the GKBA approach. In this work, we lay down a GKBA scheme that includes initial correlations in a partition-free setting. In practice, this means that the equilibration of the initially correlated and contacted molecular junction can be separated from the real-time evolution. The information about the contacted initial state is included in the out-of-equilibrium calculation via explicit evaluation of the memory integral for the embedding self-energy, which can be performed without affecting the computational scaling with the simulation time and system size. We demonstrate the developed method in carbon-based molecular junctions, where we study the role of electron correlations in transient current signatures.

Keywords: quantum physics

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 1

Last updated on 2022-14-09 at 11:46