Investigation about the coexistence between magnetism, CDW instability and superconductivity in chalcogenides of transition metals

Abstract

Preliminary results shown in this proposal with intercalation of rare earths in hosts material such as ZrTe2 and ZrTe3 reveal exotic behaviors that may indicate new ground states for these low-dimensional materials. Intercalation of transition metals such as Ni into ZrTe2 shows the coexistence between superconductivity and so call Charge density Wave CDW instability. When rare earths are intercalated in this host (ZrTe2), the superconducting transition temperature increases systematically, indicating a "chemical pressure" effect caused by the contraction of the lanthanides. More surprising is the reentrant magnetic behavior when Tb is intercalated into ZrTe3, in which the dependence on the measurement angle seems to be reflecting the enormous anisotropy of this compound. Thus, understanding these phenomena is a frontier issue that this proposal intends to help. In this context, the crystals to be grown will be made by a new method created in our research group in Lorena (EEL - USP), capable of producing huge single crystals of excellent crystallographic and chemical quality. For the development of this proposal, the main orders are: a compressor oil change, new computer for the PPMS-EverCool II installed in our department and one setup for magnetization measurements under hydrostatic pressure. In addition to the originality of the work from a scientific point of view, this project will support the training of qualified Human Resources through the training of doctoral, masters and scientific initiation students. (AU)