Tuning the Charge Density Wave and Superconductivity in CuxTaS2

K. E. Wagner; E. Morosan; Y. S. Hor; J. Tao; Y. Zhu; T. Sanders; T. M. McQueen; H. W. Zandbergen; A. J. Williams; D. V. West; R. J. Cava

doi:10.1103/physrevb.78.104520

arXiv · 0808.2147

Tuning the Charge Density Wave and Superconductivity in CuxTaS2

K. E. Wagner·E. Morosan·Y. S. Hor·J. Tao·Y. Zhu·T. Sanders·T. M. McQueen·H. W. Zandbergen·A. J. Williams·D. V. West·R. J. Cava

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Abstract

We report the characterization of layered, 2H-type CuxTaS2, for x between 0 and 0.12. The charge density wave (CDW), at 70 K for TaS2, is destabilized with Cu doping. The sub-1K superconducting transition in undoped 2H-TaS2 jumps quickly to 2.5 K at low x, increases to 4.5 K at the optimal composition Cu0.04TaS2, and then decreases at higher x. The electronic contribution to the specific heat, first increasing and then decreasing as a function of Cu content, is 12 mJ mol-1 K-2 at Cu0.04TaS2. Electron diffraction studies show that the CDW remains present at the optimal superconducting composition, but with both a changed q vector and decreased coherence length. We present an electronic phase diagram for the system.

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K. E. Wagner, E. Morosan, Y. S. Hor, J. Tao, Y. Zhu, T. Sanders, T. M. McQueen, H. W. Zandbergen, A. J. Williams, D. V. West, R. J. Cava. 2008-08-15. Tuning the Charge Density Wave and Superconductivity in CuxTaS2. https://doi.org/10.1103/physrevb.78.104520

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