Fabry-Perot superconducting diode
Abstract
Superconducting diode effects (SDEs) occur in systems with asymmetric critical supercurrents | I+c|≠| I−c| yielding dissipationless flow in one direction (e.g., +) , while dissipative transport in the opposite direction (−) . Here we investigate the SDE in a phase-biased ϕ Josephson junction with a double-barrier resonant-tunneling InAs nanowire nested between proximitized InAs/Al leads with finite momentum ℏ q Cooper pairing. Within the Bogoliubov-de Gennes (BdG) approach, we obtain the exact BCS ground state energy EG(q ,ϕ ) and I+c≠|I−c| from the current-phase relation IG(q ,ϕ ) ∼∂ϕEG(q ,ϕ ) . The SDE arises from the accrued Andreev phase shifts δ ϕL ,R(q ,ϕ ) leading to asymmetric BdG spectra for q ≠0 . Remarkably, the diode efficiency γ =( I+c−| I−c|)/( I+c+| I−c|) shows multiple Fabry-Perot resonances γ ≃26 % at the double-barrier Andreev bound states as the well depth Vg is varied. Our γ also features sign reversals for increasing q and high sensitiveness to fermion-parity transitions. The latter enables I+c(ϕ+) ⇄I−c(ϕ−) switchings over narrow phase windows, i.e., ϕ+,ϕ−∈Δ ϕ ≪π , possibly relevant for future superconducting electronics.
- Publication:
-
Physical Review B
- Pub Date:
- May 2024
- DOI:
- 10.1103/PhysRevB.109.184513
- arXiv:
- arXiv:2404.08962
- Bibcode:
- 2024PhRvB.109r4513Z
- Keywords:
-
- Condensed Matter - Superconductivity
- E-Print:
- 29 pages, 12 figures