The innovation engine for new materials

Viktor Bekassy

Viktor Bekassy

University: 

Chalmers University of Technology

Major: 

Physics

Mentor(s): 

Andrea Capa Salinas

Faculty Sponsor(s): 

Stephen Wilson

Faculty Sponsor's Department: 

Materials

Project Title: 

Tuning Superconductivity and Charge Density Wave Transition by Straining in Kagome Metals CsV3Sb5-xSnx and RbV3Sb5-xSnx

Project Description: 

Recent discovery of the family AV3Sb5, (A = K, Rb, Cs) of kagome metals provide an unprecedented opportunity to study nontrivial band topology, superconducting ground states, and  correlated electronic behavior in form of a charge density wave order. These materials feature a two-dimensional kagome net of vanadium atoms and provide an opportunity to learn about the relationship between charge order and superconductivity on a kagome lattice structure. Here, we investigate the change in superconducting transition temperature TC and charge density wave transition temperature T* of tin doped kagome metals CsV3Sb5-xSnx and RbV3Sb5-xSnx

upon uniaxial strain. Single crystals are synthesized via the flux method and characterized using scanning electron microscopy (SEM), X-ray diffraction, Laue diffraction, and Magnetic Properties Measurement System (MPMS). Using a Razorbill stress cell and electrical resistivity measurements, we are able to follow the evolution of TC and T* while straining our samples. With the application of strain on CsV3Sb5, our initial results suggest that TC  monotonically increase whereas T* show a more non-trivial behavior. Future work involve further straining CsV3Sb5 to better quantify the behavior of  T* , and straining doped crystals. Furthermore, comparison between different kagome metals, and between different dopant concentrations will be made. Our results will provide an insight into the dependance of superconductivity and charge density wave order upon applied uniaxial strain to kagome metals and can contribute to the understanding of underlying physics in related materials.