Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop

Golibjon Berdiyorov, S. H. Yu, Z. L. Xiao, F. M. Peeters, J. Hua, A. Imre, W. K. Kwok

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19 Citations (Scopus)


We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures.

Original languageEnglish
Article number064511
JournalPhysical Review B - Condensed Matter and Materials Physics
Issue number6
Publication statusPublished - 17 Aug 2009
Externally publishedYes


ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

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