Dicke-Josephson effect in a cross-typed triple-quantum-dot junction. (December 2016)

• Record Type: Journal Article
• Authors: Wang, Xiao-Qi; Yi, Guang-Yu; Gong, Wei-Jiang
• Is Part Of: Solid state communications. Volume 247(2016)
• Page Start: 12
• Page End: 16
• Publication Date: 2016-12
• Subjects: A. Quantum dot -- B. Dicke effect -- D. Josephson current; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2016.08.011
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: We investigate the Dicke-Josephson effect in a superconductor/triple-quantum-dot/superconductor junction in which the central dot is coupled to the superconductors. It is found that the Dicke effect can modulate the Josephson effect in a nontrivial way. In the noninteracting case, the Dicke effect induces a subpeak in the supercurrent spectrum around the energy zero point. When intradot interactions are taken into account, the role of the Dicke effect changes completely. Namely, it tends to suppress the π -phase current near the position of electron-hole symmetry. With the increase of the Coulomb strength, it has an opportunity to reverse the current direction. We thus conclude that the Dicke-Josephson effect is also an important part in describing the Josephson effect in coupled-dot junctions. Abstract : Highlights: We study Dicke-Josephson effect in a S/TQD/S junction with central QD coupled to superconductors. In the noninteracting case, Dicke effect induces a subpeak in the supercurrent spectrum. When intradot interactions are considered, Dicke effect suppresses the pi-phase current. Dicke effect can reverse the current direction following the increase of Coulomb strength. The Dicke-Josephson effect should be an important part in describing the Josephson effect.