Robust bulk superconductivity by giant proximity effect in Weyl semimetal-superconducting NbP/NbSe₂ composites

We synthesize the Weyl semimetal/superconductor NbP/NbSe 2 composite and observe stable bulk superconductivity at T c = 7.2, 6.9, 6.8 K for NbSe crystal, (1:1), (2:1) composites, respectively, despite large volume fraction of non-superconducting NbP phase. From Ginzburg–Landau theory, H c2 (0) is significantly enhanced in composites [22 (1:1) 18.5 (2:1)] comparing with pristine crystal (8 T). The cannot be simply described by de Gennes–Meissner theory a proximity effect. electrical transport, magnetization, heat capacity measurement, we obtain various superconducting parameters. properties indicate that far from conventional Bardeen–Cooper–Schrieffer superconductivity. It suggests can have giant effect, resulting sizable semimetals. effect interface platform to investigate induced semimetallic states.