Interstitial anionic electrons involved superconductivity and T-linear resistivity behavior in electride La3In

TL;DR

This study reports the discovery of superconductivity at 9.4 K and T-linear resistivity in La3In electride crystals, highlighting the role of interstitial anionic electrons in these phenomena and their potential for high-temperature superconductivity.

Contribution

It provides the first detailed experimental and theoretical analysis of superconductivity and normal-state properties in single-crystal La3In electride, emphasizing the influence of IAEs.

Findings

La3In exhibits type-II superconductivity with Tc ~ 9.4 K.

The material shows T-linear resistivity over a wide temperature range.

High density of states and electron-phonon coupling linked to IAEs may explain the high Tc.

Abstract

Electrides are unique materials because of the existence of interstitial anionic electrons (IAEs). Due to these loosely bound IAEs and their strong interaction with the framework of cations, electrides can host superconductivity with rather high Tc, especially under high pressure, as predicted in theory. However, the experimental observations of superconductivity in electrides are very rare, let alone the detailed studies on intrinsic properties of single crystals. Here, we report the superconducting and normal-state properties of electride La3In single crystals. La3In shows a type-II superconductivity with Tc ~ 9.4 K and a T-linear resistivity in a wide temperature range. Experimental measurements and theoretical calculations suggest that the relatively high Tc could be ascribed to the high density of states around the Fermi level caused by short flat bands along R-M direction and the strong electron-phonon coupling, partially derived from the IAEs. Meanwhile, the T-linear resistivity may reflect the significant electronic correlation effect in this material. These findings will shed light on understanding the role of IAEs in superconductivity and open a promising way to explore high-temperature superconductors in electrides.