Generalized atomic limit of a double quantum dot coupled to superconducting leads

0571616 - FZÚ 2024 RIV US eng J - Journal Article
Žonda, M. - Zalom, Peter - Novotný, T. - Loukeris, G. - Baetge, J. - Pokorný, Vladislav
Generalized atomic limit of a double quantum dot coupled to superconducting leads.
Physical Review B. Roč. 107, č. 11 (2023), č. článku 115407. ISSN 2469-9950. E-ISSN 2469-9969
EU Projects: European Commission(XE) CA21144 - SUPERQUMAP
Research Infrastructure: e-INFRA CZ - 90140
Institutional support: RVO:68378271
Keywords : nanoscopic superconductivity * quantum dots * effective models * Andreev reflection * Josephson current
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.7, year: 2022
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevB.107.115407

We present an exactly solvable effective model of a double quantum dot coupled to superconducting leads. This model is a generalization of the well-known superconducting atomic limit approximation of the paradigmatic superconducting impurity Anderson model. However, in contrast to the standard atomic limit and other effective models, it gives quantitatively correct predictions for the quantum phase transition boundaries, subgap bound states as well as Josephson supercurrent in a broad range of parameters including experimentally relevant regimes. The model allows fast and reliable parameter scans important for the preparation and analysis of experiments, which are otherwise inaccessible by more precise but computational heavy methods such as quantum Monte Carlo or the numerical renormalization group. The scans also allowed us to identify and investigate new previously unnoticed phase diagram regimes.
Permanent Link: https://hdl.handle.net/11104/0346760