Signature of Unconventional Superconductivity in a Copper-based Metal-Organic Framework with Perfect Kagome Structure
Abstract
Recently, the superconductivity in a metal-organic framework (MOF) has been discovered for the first time in copper(II) benzenehexathiolate ([Cu$_3$(C$_6$S$_6$)]$_n$, Cu-BHT). The Cu atoms form a two-dimensional perfect Kagome lattice, which has the potential to host a metallic quantum spin liquid state. Here we present high-precision measurements of in-plane magnetic penetration depth $\lambda$ in Cu-BHT films down to 40\,mK. The temperature dependence of $\lambda$ shows a non-exponential, quasi-linear behavior at low temperatures, suggesting that unconventional superconductivity with low-energy quasiparticle excitations is realized in this system. With the reported non-Fermi liquid behavior, this finding implies that MOFs can provide a flexible platform to investigate the superconducting pairing mechanisms in the presence of spin frustration and strong quantum fluctuations.
- Publication:
-
arXiv e-prints
- Pub Date:
- October 2018
- DOI:
- 10.48550/arXiv.1810.00569
- arXiv:
- arXiv:1810.00569
- Bibcode:
- 2018arXiv181000569T
- Keywords:
-
- Condensed Matter - Superconductivity;
- Condensed Matter - Materials Science
- E-Print:
- We have added new experimental inputs a lot and modified some analytical method. The structure of the paper has changed significantly, so we want to withdraw it first