Intermediate type-I superconductors in the mesoscopic scale

Author(s)

Cadorim, Leonardo R. ; Romaguera, Antonio R. de C. ; de Oliveira, Isaias G. ; Gomes, Rodolpho R. ; Doria, Mauro M. ; Sardella, Edson

• Document type: Journal article
• Source: PHYSICAL REVIEW B; v. 103, n. 1, p. 6-pg., 2021-01-07.

Abstract

M. Tinkham [Introduction to Superconductivity, 2nd ed. (Dover, Mineola, NY, 2004), Chap. 4, pp. 135-138] and P. G. de Gennes [Superconductivity of Metals andAlloys (Benjamin, New York, 1966), Chap. 6, pp. 199-201] described the existence of an intermediate type-I superconductor as a consequence of an external surface that affects the well-known classification of superconductors into type I and II. Here we consider the mesoscopic superconductor where the volume-to-area ratio is small and the effects of the external surface are enhanced. By means of the standard Ginzburg-Landau theory, the Tinkham-de Gennes scenario is extended to the mesoscopic type-I superconductor. We find additional features of the transition at the passage from the genuine to the intermediate type I. The latter has two distinct transitions, namely from a paramagnetic to diamagnetic response in descending field, and a quasi-type-II behavior as the critical coupling 1/root 2 is approached in ascending field. The intermediate type-I phase proposed here, and its corresponding transitions, reflect intrinsic features of the superconductor and not its geometrical properties. (AU)

• FAPESP's process: 12/04388-0 - Tridimensional simulations of the demagnetization effects in nanostructured superconducting films
• Grantee: Edson Sardella
• Support Opportunities: Regular Research Grants
• FAPESP's process: 20/03947-2 - Characterization of magnetic and electronic properties in mesoscopic and nanostructured multiband superconductors
• Grantee: Leonardo Rodrigues Cadorim
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)