Numerical modelling of the charge density wave state in TiSe2

The charge density wave (CDW) is an example of a low temperature phase of matter which occurs due to strongly correlated electrons. CDW materials are characterised by a periodic distortion of the atomic lattice, periodic modulation of the electronic charge distribution, and a complex order parameter. These materials have potential application in mechanical vibration detectors, optoelectric devices, information processing, memory, and many other next generation technologies. Many strongly correlated materials show non-trivial phases at similar temperatures and energy scales, and because of this, disentangling the mechanisms behind the phases has historically proven difficult using standard many-body methods. Here we use dynamical mean-field theory (DMFT), density functional theory (DFT), and time-dependent Ginzburg-Landau (TDGL) formalism to investigate the electronic properties of the CDW material TiSe2. Using these numerical techniques, we can understand both the formation of the CDW state and the melting of this phase due to the application of laser pulses and the resulting heating of the phononic environment.

About the presenter

Joshua Gray is a PhD Student at RMIT with CI Jared Cole. His project explores ultra-fast spectroscopy of strongly correlated materials, as part of FLEET’s Research Theme 1, Topological Materials.