Univ. Paris-Saclay

Service de Physique de l'Etat Condensé

Ultimate Vortex Confinement Studied by Scanning Tunneling Spectroscopy
Dimitri Roditchev
Institut des Nanosciences de Paris
Mercredi 09/12/2009, 11:15
SPEC Salle Itzykson, Bât.774, Orme des Merisiers

We report a detailed scanning tunneling microscopy study of a superconductor in a strong vortex confinement regime. This is achieved in a thin nano-island of Pb having a size d about 2-3 times the effective coherence length, and a thickness h such that h << d << λ , where λ is the effective London penetration depth. In this geometry the magnetic field evolution of local tunneling spectra reveals only two superconducting configurations to exist: zero and single vorticity. The normal state is reached at HC ≈ 0.46 T, about 6 times the critical field of bulk Pb, with no higher order vorticity observed [1]. The comparison of the acquired Scanning Tunneling Spectroscopy data with the numerically resolved Usadel equations allowed us to reveal the fundamental role played in both configurations by the circulating supercurrents.

[1] T. Cren et al., Phys. Rev. Lett. 102, 127005 (2009).

Contact : Ivan DORNIC


Retour en haut