2H-NbSe2 is one of the most widely researched transition metal dichalcogenide (TMD) superconductors, which undergoes charge-density wave (CDW) transition at TCDW about 33 K and superconducting transition at Tc of 7.3 K. To explore the relation between its superconductivity and Fermi surface nesting, we combined S substitution with Cu intercalation in 2H-NbSe2 to make CuxNbSe2-ySy. Upon systematic substitution of S and intercalation of Cu ions into 2H-NbSe2, we found that when the Cu and S contents increases, the Tc decreases in CuxNbSe2-ySy. While at higher x and y values, Tc keeps a constant value near 2 K, which is not commonly observed for a layered TMD. For comparison, we found the simultaneous substitution of Nb by Cu and Se by S in CuxNb1-xSe2-ySy lowered the Tc substantially faster. We construct a superconducting phase diagrams for our double-doping compounds in contrast with the related single-ions doping systems.
@article{arxiv.1907.01776,
title = {The Unusual Suppression of Superconducting Transition Temperature in Double-Doping 2H-NbSe$_2$},
author = {Dong Yan and Yishi Lin and Guohua Wang and Zhen Zhu and Shu Wang and Lei Shi and Yuan He and Man-Rong Li and Hao Zheng and Jie Ma and Jinfeng Jia and Yihua Wang and Huixia Luo},
journal= {arXiv preprint arXiv:1907.01776},
year = {2019}
}
Comments
20 pages, 6 figures, post-print of the article published in the Superconductor Science and Technology (2019)