2025/05/27 by Risa Ogino, Ogino, Risa, Shun Uchino +1 · 3 citations
Physics and Astronomy · #Quantum, superfluid, helium dynamics #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories
paper · pdf · doi:10.48550/arxiv.2505.21085
We show that supercurrent properties in a superfluid or superconducting junction are significantly modified due to single-particle losses present in a conduction channel. In the presence of a spin-independent particle loss, we find regimes where the Josephson current IN(ϕ) takes zero at a position in between ϕ= 0 and ϕ=π, and the direction of the supercurrent is reversed. Although the region is narrow, we also find a regime in which the critical current is enhanced by dissipation. Such anomalous behaviors in the Josephson current are attributed to a subtle interplay between the contribution that is present regardless of dissipation and the unconventional one that is absent without dissipation. In the presence of a spin-selective particle loss, it is shown that a dissipation-induced spin supercurrent and its reversal occur. The proposed system is analyzed by means of the Keldysh field theory approach based on the Gorini-Kossakowski-Sudershan-Lindblad master equation and may be realized in ultracold atomic gases and solid-state systems.