### FERMI SURFACE AND LIFSHITZ TRANSITION IN KAGOME METALS

2018

A large number of theoretical and experimental work is going on to find Lifshitz Transition(LT) in different materials. LT is observed in many real systems such as heavy fermions, iron based superconductors. Application of magnetic field, external pressure and doping can cause change in topology of FS. Kagome lattice(KL) is given emphasis in this research work to study possible LT. Exotic electronic and quantum magnetic properties is exhibited by KL when individual atom of conductive material could be arranged in triangular pattern resembling kagome pattern. Density functional theory (DFT) calculation will be used for studying FS of kagome material. The accurate first principles calculation applying DFT based band structure code FPLO will be used. We are interested to study semimetals properties of KL.

This work will be based on theoretical calculation of LT of KL during shifting from type I to type II weyl points. FS properties along with scalar relativistic band structure calculation is to be focused. Full relativistic calculation and wannier Hamiltonian will be defined in FPLO along with tight binding calculations. Berry curvature of KL is intended to compute for investigating anamolous hall effect (AHE) and quantum AHE. Superconducting transition temperature can be increase through transition-related singularities. In our universe the small masses of elementary particle can be possibly originated by consequences of LT.