Degree Name

Doctor of Philosophy


School of Physics


In this thesis, we examine five main transport properties: nonlinear optical conductivity, self-focusing, thermionic conductivity, photogalvanic conductivity and magneto-optical conductivity across a number of topological materials. In the case of Weyl, Dirac and gapped semimetals as well as the α-T3 model, minimal coupling Hamiltonia are able to capture multiple topological phases through the same equation. This allows us to survey nonlinear optical conductivity, self-focusing and thermionic conductivity for the nodal semimetals whilst only nonlinear conductivity is studied for the α-T3 lattice. Shift current generation and circularly polarised photogalvanic conductivity are uncovered for a symmetry broken nodal ring material whilst twisted bilayer graphene is the system in which we study both nonlinear and magneto-optical conductivity.

FoR codes (2008)

020404 Electronic and Magnetic Properties of Condensed Matter; Superconductivity, 020503 Nonlinear Optics and Spectroscopy



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.