Interplay of Meissner Currents and Magnetic Vortices in NbSe2 Probed by Tunneling Spectroscopy

Mapping edge supercurrents in thin superconducting films and resolving the Meissner and vortex contributions provide important insights into the nature of type II two-dimensional superconductors. Here, we perform tunneling spectroscopy measurements on thin exfoliated NbSe2 flakes to probe Doppler shifts of the quasiparticle density of states and extract the current density at the flake edge with a resolution of 5–10 μA/μm. We observe a distinct hysteretic response of the tunneling spectra under small out-of-plane magnetic fields, allowing a deconvolution of the Meissner and vortex current contributions. The isolated contributions of Meissner currents to the Doppler shift are corroborated using a numerical solution of the London equations. Our results demonstrate that tunneling devices are highly effective for monitoring non-equilibrium and dynamical effects in thin superconducting films.