par De Wilde, Yannick ;Iavarone, Maria;Welp, Ulrich W.;Metlushko, Vitali;Koshelev, Alexei E.;Aranson, Igor S.;Crabtree, George W.;Canfield, Paul C.
Référence Physical review letters, 78, 22, page (4273-4276)
Publication Publié, 1997-06-02
Référence Physical review letters, 78, 22, page (4273-4276)
Publication Publié, 1997-06-02
Article révisé par les pairs
Résumé : | We present scanning tunneling microscopy measurements of the (001) surface of a LuNi2B2C borocarbide single crystal at 4.2 K. In zero field, the conductance versus voltage characteristics recorded at various locations on the sample reproducibly provide a gap value of 2.2 meV. In a magnetic field of 1.5 and 0.375 T, the recordings of the conductance as a function of position reveal a regular square vortex lattice tilted by 45° with respect to the crystalline a axis. This unusual result is correlated with an in-plane anisotropy of the upper critical field Hc2∥(45°)/Hc2∥(0) = 0.92 at 4.2 K and is analyzed within the framework of Ginzburg-Landau theory. |