کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1817400 | 1525691 | 2016 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Edge effect and significant increase of the superconducting transition onset temperature of 2D superconductors in flat and curved geometries Edge effect and significant increase of the superconducting transition onset temperature of 2D superconductors in flat and curved geometries](/preview/png/1817400.png)
• The superconducting transition temperature Tc in the case of a 2D rectangular sheet, a hollow cylinder and a hollow sphere of one coherence length thickness is compared.
• Being extremely thin in a flat rectangular shape is not enough to significantly enhance the Tc through phonon softening unless a curvature is added.
• The edge effect of such a 2D sheet has a strong broadening effect on Tc in addition to the effect of order parameter phase fluctuations.
In this paper, we present a simple method to model the curvature activated phonon softening in a 2D superconducting layer. The superconducting transition temperature Tc in the case of a 2D rectangular sheet, a hollow cylinder and a hollow sphere of one coherence length thickness is calculated by the quantum mechanical electron–phonon scattering matrix, and a series of collective lattice vibrations in the surface state. We will show that being extremely thin in a flat rectangular shape is not enough to significantly enhance the Tc through phonon softening. However, if a curvature is added, Tc can be strongly enhanced. The increase in Tc with respect to the bulk is greatest in a hollow sphere, intermediate in a hollow cylinder and weakest for the rectangular sheet, when systems of identical length scale are considered. In addition, we find that the edge effect of such a 2D sheet has a strong broadening effect on Tc in addition to the effect of order parameter phase fluctuations.
Journal: Physica C: Superconductivity and its Applications - Volumes 521–522, 15 February 2016, Pages 50–54