Charge density wave (CDW), the periodic modulation of the electronic charge density, will open a gap on the Fermi surface that commonly leads to decreased or vanishing conductivity. On the other hand superconductivity, a commonly believed competing order, features a Fermi surface gap that results in infinite conductivity. Here we report that superconductivity emerges upon Se doping in CDW conductor ZrTe3 when the long range CDW order is gradually suppressed. Superconducting critical temperature Tc(x) in ZrTe3−xSex (0≤x≤0.1) increases up to 4 K plateau for 0.04≤x≤0.07. Further increase in Se content results in diminishing Tc and filametary superconductivity. The CDW modes from Raman spectra are observed in x = 0.04 and 0.1 crystals, where signature of ZrTe3 CDW order in resistivity vanishes. The electronic-scattering for high Tc crystals is dominated by local CDW fluctuations at high temperures, the resistivity is linear up to highest measured T=300K and contributes to substantial in-plane anisotropy.
@article{arxiv.1606.02284,
title = {Superconductivity and Charge Density Wave in ZrTe$_{3-x}$Se$_{x}$},
author = {Xiangde Zhu and Wei Ning and Lijun Li and Langsheng Ling and Ranran Zhang and Jinglei Zhang and Kefeng Wang and Yu Liu and Li Pi and Yongchang Ma and Haifeng Du and Minglian Tian and Yuping Sun and Cedomir Petrovic and Yuheng Zhang},
journal= {arXiv preprint arXiv:1606.02284},
year = {2016}
}