# Doping-induced superconductivity in the van der Waals superatomic   crystal Re$_6$Se$_8$Cl$_2$

**Authors:** Evan J. Telford, Jake C. Russell, Joshua R. Swann, Brandon Fowler,, Xiaoman Wang, Kihong Lee, Amirali Zangiabadi, Kenji Watanabe, Takashi, Taniguchi, Colin Nuckolls, Patrick Batail, Xiaoyang Zhu, Jonathan A. Malen,, Cory R. Dean, Xavier Roy

arXiv: 1906.10785 · 2020-04-22

## TL;DR

This study demonstrates that doping via Cl dissociation induces superconductivity in the two-dimensional superatomic crystal Re$_6$Se$_8$Cl$_2$, marking the first such observation in a van der Waals superatomic material.

## Contribution

It introduces a novel chemical doping method to induce superconductivity in van der Waals superatomic crystals, expanding the potential for electronic applications.

## Key findings

- Doping transforms Re$_6$Se$_8$Cl$_2$ from semiconductor to superconductor.
- Superconductivity observed below approximately 9 K.
- Doping achieved through Cl dissociation using in situ current annealing.

## Abstract

Superatomic crystals are composed of discrete modular clusters that emulate the role of atoms in traditional atomic solids$^{1-4}$. Owing to their unique hierarchical structures, these materials are promising candidates to host exotic phenomena, such as superconductivity and magnetism that can be revealed through doping$^{5-10}$. Low-dimensional superatomic crystals hold great promise as electronic components$^{11,12}$, enabling these properties to be applied to nanocircuits, but the impact of doping in such compounds remains unexplored. Here we report the electrical transport properties of Re$_6$Se$_8$Cl$_2$, a two-dimensional superatomic semiconductor$^{13,14}$. Using an in situ current annealing technique, we find that this compound can be n-doped through Cl dissociation, drastically altering the transport behaviour from semiconducting to metallic and giving rise to superconductivity below $\sim$ 9 K. This work is the first example of superconductivity in a van der Waals (vdW) superatomic crystal; more broadly, it establishes a new chemical strategy to manipulate the electronic properties of vdW materials with labile ligands.

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Source: https://tomesphere.com/paper/1906.10785