2022/09/26 by Da Wang, Wang, Da, Qiang-Hua Wang +3 · 3 citations
Engineering · Physics and Astronomy · #Advanced Electrical Measurement Techniques #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.2209.12646
openalex publication_date 2022/09/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is necessary to break both time-reversal and parity symmetries to realize a Josephson, or superconducting, diode exhibiting nonreciprocal critical direct-currents (DC). In fact, these conditions are still insufficient. The dependencies of the free energy on the phase difference across the junction and the magnetic field are classified, exhibiting the current-reversion (JR), field-reversion, and field-current reversion conditions, respectively. To exhibit the DC Josephson diode effect, all symmetries satisfying the JR condition need to be broken. The relations of critical currents with respect to the magnetic field are classified into five classes, including three exhibiting the diode effect. These symmetry considerations are applied to concrete examples. Our work reveals that the DC Josephson diode effect is a natural consequence of the JR symmetry breaking, hence, providing a guiding principle to understand or design a DC Josephson diode.