Influence of trapped magnetic field of Sn-Pb solders on electrical resistivity measurement: an example of superconducting transition of Sn

TL;DR

This study investigates how trapped magnetic flux in Sn-Pb solders influences the superconducting transition of Sn, highlighting the importance of magnetic history in electrical resistivity measurements.

Contribution

It demonstrates the impact of flux-trapped states on superconducting properties and emphasizes considering magnetic history in resistivity measurements of solders.

Findings

Zero-field cooling shows sharp superconducting transition at 3.7 K.

Field cooling broadens the superconducting transition.

Trapped flux critically affects superconducting states in solders.

Abstract

We examined the affection of the flux-trapped states of Sn60-Pb40 solders on superconducting properties of a Sn wire. The temperature dependence of electrical resistivity at H = 0 Oe after zero-field cooling (ZFC) showed a sharp superconducting transition at T = 3.7 K. In contrast, that after field cooling (FC) resulted in broadening of the transition. The difference between ZFC and FC data evidences critical affection of trapped fluxes at solders on superconducting states. We propose that, in electrical measurements where magnetic fields of several hundred Oe are critical, field experience should be seriously considered when using solders.