2001/08/09 by Qing‐Feng Sun, Qing-feng Sun, Hong Guo +1 · 1 citation
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.65.075315
published as Physics Review B 65, 075315(2002) · 23 pages, 10 figures, LaTex
arxiv created 2001/08/09 · openalex publication_date 2002/01/30 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The ac Josephson effect in hybrid systems of a normal mesoscopic conductor coupled to two superconducting (S) leads is investigated theoretically. A general formula of the ac components of time-dependent current is derived which is valid for arbitrary interactions in the normal region. We apply this formula to analyze a S-normal-S system where the normal region is a noninteracting single level quantum dot. We report the physical behavior of time-averaged nonequilibrium distribution of electrons in the quantum dot, the formation of Andreev bound states, and ac components of the time-dependent current. The distribution is found to exhibit a population inversion; and all Andreev bound states between the superconducting gap Δ carry the same amount of current and in the same flow direction. The ac components of time-dependent current show strong oscillatory behavior in marked contrast to the subharmonic gap structure of the average current.