Oscillations of critical superconducting current in thin doubly-connected Sn films in an external perpendicular magnetic field

Autor: A. M. Glukhov, A. G. Sivakov, A. N. Omelyanchouk, A. S. Pokhila, S. V. Kuplevakhsky
Rok vydání: 2014
Předmět:
Zdroj: Low Temperature Physics. 40:408-417
ISSN: 1090-6517
1063-777X
Popis: We report the results of experimental and theoretical studies of critical current oscillations in thin doubly-connected Sn films in an external perpendicular magnetic field. The experiments were performed on samples that consisted of two wide electrodes joined together by two narrow channels. The length of the channels l satisfied the condition l ≫ ξ (ξ is the Ginzburg–Landau coherence length). At temperatures close to the critical temperature Tc, the dependence of the critical current Ic on average external magnetic flux Φ¯e has the form of a piecewise linear function, periodic with respect to the flux quantum Φ0. The amplitude of the Ic oscillation at a given temperature is proportional to the factor ξ/l. Moreover, the dependence Ic=Ic(Φ¯e) is found to be multivalued, hence indicating the presence of metastable states. Based on the Ginzburg–Landau approximation, a theory was constructed that explains the above features of the oscillation phenomenon taking a perfectly symmetric system as an example. Furt...
Databáze: OpenAIRE