Evidence for High Tc Superconducting Transitions in Isolated Al45- and Al47- Nanoclusters

TL;DR

This study provides experimental evidence of high-temperature superconducting transitions in isolated Al45- and Al47- nanoclusters, aligning with theoretical predictions of superconductivity in clusters with degenerate electronic states.

Contribution

It presents the first experimental observation of high Tc superconducting transitions in specific aluminum nanoclusters, confirming theoretical models.

Findings

Heat capacity jumps at ~200 K indicate superconducting transitions.

Experimental data matches theoretical predictions of critical temperature.

Clusters exhibit size-dependent superconducting behavior.

Abstract

Heat capacities measured for Al45- and Al47- nanoclusters have reproducible jumps at ~ 200 K. These jumps are consistent with theoretical predictions that some clusters with highly degenerate electronic states near the Fermi level will undergo a transition into a high Tc superconducting state. An analysis based on a theoretical treatment of pairing in Al45- and Al47- agrees well with the experimental data in both the value of the critical temperature and in the size and width of the jumps in the heat capacity.