Effect of replacement of tellurium by selenium on the superconducting behavior of the stoichiometric ZrTe2 Dirac semimetal.

• Grant number: 23/09555-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2023
• End date: August 31, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Antonio Jefferson da Silva Machado
• Grantee: Vitor Mascarello Fim
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil

Abstract

Recently, our research group demonstrated that tellurium deficiency in the Dirac semimetal of ZrTe2 composition induces superconductivity around 3.3 K. Thus, this work plan deals with the study of the superconductivity that emerges from the replacement of Te by Se in host material on ZrTe2-xSex stoichiometry. The preliminary results presented in this work plan show that the first substitution attempted in a single crystal of ZrTe1.8Se0.2 composition causes superconductivity to emerge in the vicinity of 4.2 K. This preliminary result shows that the superconductivity in this Dirac semimetal with topology does not trivial, is extremely dependent on defects at the Te site. Thus, the work plan presented below intends to carry out a systematic study of the replacement of Te by Se to better understand the impact of such substitution on the electronic properties of this host material (ZrTe2). The possibility of an unconventional superconducting state is a very reasonable hypothesis and needs to be studied. In addition to the scientific aspects addressed here, this work plan intends to expand the student's training with regard to problems of synthesis and characterization of new materials.