New Editors’ Suggestion: Proposal for Detection of the 0′ and π′ Phases in Quantum-Dot Josephson Junctions

We are pleased to announce our latest article and thank the APS for considering it an Editors’ Suggestion on PRL. Congrats, everyone!

Minchul Lee, Rosa López, H. Q. Xu, and Gloria Platero

Phys. Rev. Lett. 129, 207701

The competition between the Kondo correlation and superconductivity in quantum-dot Josephson junctions (QDJJs) has been known to drive a quantum phase transition between 0 and $\pi$ junctions. Theoretical studies so far have predicted that under strong Coulomb correlations the $0\text{−}\pi$ transition should go through intermediate states, $0^{\prime }$ and ${\pi }^{\prime }$ phases. By combining a nonperturbative numerical method and the resistively shunted

junction model, we investigated the magnetic-field-driven phase transition of the QDJJs in the Kondo regime and found that the low-field magnetotransport exhibits a unique feature which can be used to distinguish the intermediate phases. In particular, the magnetic-field driven ${\pi }^{\prime }\text{−}\pi$ transition is found to lead to the enhancement of the supercurrent which is strongly related to the Kondo effect.