Ladění terahertzové odezvy dielektrických materiálů a metamateriálových struktur

As a result of the ongoing progress of terahertz technologies, opportunities to use novel and actively tunable components for emerging applications are expected. The project will investigate ferroelectric materials exhibiting a strong dependence of the dielectric function on external parameters, especially electric bias. We will mainly focus on perovskite oxide ferroelectrics (bulk crystals, ceramics and thin films), where understanding of the lattice anharmonicity is crucial for the enhancement of their dielectric tuning, and where their chemical composition can be smoothly varied and used for the optimization of their properties. These materials will be combined with metamaterial concepts and employed to develop tunable THz photonic components, including those with a negative effective permeability or a negative refractive index. The experimental characterization will be performed by time-domain terahertz spectroscopy; electromagnetic simulations will be conducted in order to understand the wave propagation through the structures and to optimize their response.