Possibility of Exciton Mediated Superconductivity in Nano-Sized Sn/Si Core-Shell Clusters: A Process Technology towards Heterogeneous Material in Nano-Scale

TL;DR

This study demonstrates superconductivity in Sn/Si core-shell clusters at low temperatures, suggesting exciton-mediated mechanisms could enable nano-scale heterostructure superconductors.

Contribution

It provides experimental evidence of exciton-mediated superconductivity in nano-sized Sn/Si clusters, a novel approach in heterostructure material design.

Findings

Superconductivity observed below 6.1 K in Sn/Si clusters.

Meissner effect confirmed in samples with 8 at.% Si.

Transition temperature potentially enhanced by exciton mechanisms.

Abstract

We have produced Sn/Si core-shell cluster assemblies by a plasma-gas-condensation cluster beam deposition apparatus. For the sample with Si content = 12 at.%, the temperature dependence of electrical resistivity exhibits a metallic behavior above 10K and the onset of superconducting transition below 6.1 K. With decreasing temperature, the thermomagnetic curve for the sample with Si content = 8 at.% begins to decrease steadily toward negative value below 7.7 K, indicating the Meissner effect. An increase in the transition temperature, TC is attributable to exciton-typesuperconductivity.