Research overview
This PhD thesis develops thin-film terahertz transmission measurements to resolve the vibrational anisotropy of high-quality layered (2D) hybrid perovskites. It describes building a broadband terahertz time-domain spectrometer from scratch, with generalised models of THz propagation through thin films. It then optimises spin-coating synthesis of uniform perovskite films, finding that the best conditions depend on composition. An oblique-incidence, polarization-resolved THz transmission method then reveals previously unseen vibrational excitations in 2D hybrid perovskites, which are relevant to their photophysics. The work aims to make THz spectroscopy more accessible as a tool for perovskite materials used in renewable energy.
Key findings
- Broadband THz time-domain spectrometer built from scratch, with thin-film propagation models
- Spin-coating conditions for uniform perovskite films depend on composition
- Oblique-incidence, polarization-resolved THz transmission resolves vibrational anisotropy
- Previously unseen vibrational excitations found in 2D hybrid perovskites
