High efficiency superconducting diode effect in a gate-tunable double-loop SQUID
- Wyatt Gibbons ,
- Teng Zhang ,
- Kevin Barrow ,
- T. Lindemann ,
- Jukka Vayrynen ,
- Professor Michael J Manfra
arXiv
In superconducting quantum interference devices (SQUIDs), the superconducting diode effect may be generated by interference of multiple harmonic components in the current-phase relationships (CPRs) of different branches forming SQUID loops. Through the inclusion of two gate-tunable Josephson junctions in series in each interference branch of a double-loop SQUID, we demonstrate independent control over both the harmonic content and the amplitude of three interfering CPRs, facilitating significant improvement in the maximum diode efficiency. Through optimized gate-controlled tuning of individual Josephson energies, diode efficiency exceeding 50% is demonstrated. Flux-dependent oscillations show quantitative agreement with a simple model of SQUID operation.