Relationship between charge density wave, filamentary superconductivity and bulk superconductivity in ZrTe3

We investigated the relationship between a charge density wave (CDW) with a transition temperature (T-CDW) of similar to 60 K, filamentary superconductivities (SCs) along the a-axis and the b-axis with transition temperatures (T-C's) of similar to 3.5K, and a bulk SC with a T-C below 2.5K in ZrTe3, by measuring electrical resistance and magnetization for several crystals synthesized at different growth temperatures. As the growth temperature increased, the T-CDW decreased, the T-C of the bulk SC increased, and the T-C's of the filamentary SCs did not show a clear change. The anisotropy of the upper critical field (H-C2) was different between the filamentary SCs and the bulk SC. These differences in the growth temperature dependence of T-C and the anisotropy of H-C2 indicate that the filamentary SCs are unrelated to the bulk SC. Moreover, the growth temperature dependence of the transition temperatures indicates that the CDW has a competitive relationship with the bulk SC, but a non-competitive coexistence with the filamentary SCs. Based on the anisotropies of H-C2, we also infer that the filamentary SCs and the bulk SC occur on quasi-one-dimensional Fermi surfaces and a three-dimensional Fermi surface, respectively, and that the relationship between the three states in ZrTe3 cannot be explained solely in terms of conventional competition for a Fermi surface. Copyright (C) 2021 The author(s) Published by the EPLA under the terms of the Creative Commons Attribution 4.0 International License (CC BY).

Automated summary

In ZrTe3, different growth temperatures affect the transition temperatures of CDW, bulk SC, and filamentary SCs, with differences observed in the anisotropy of the upper critical field between filamentary SCs and bulk SC.