PhD in Physics And Astronomy

This project will focus on designing and testing terahertz (THz) light modulators and manipulators using microstructured materials combined with liquid crystals. It will explore how such systems can resonantly amplify THz field, causing the adjacent layer of liquid crystals to locally reorient thus changing the optical transmission and beam path. Spectroscopy using the THz region of spectrum is expanding rapidly into a wide range of applications in sensing, wireless communication and imaging. However, the main challenge is to develop an efficient way to manipulate free-space THz beams given that the methods and materials used for other wavelengths are typically not suitable, namely have limited THz response. Recently, we demonstrated that thin liquid crystals are among the few materials that can be used as wave retarders for bright THz radiation. This project will focus on designing and testing THz light modulators and beam steering systems that combine microstructured materials with an added tuneable element made of liquid crystals. The experimental research will build upon our expertise in contactless THz switching. For example, we will explore how the resonant amplification of THz fields by metallic micro-structured materials can lead to the adjacent layer of liquid crystals to locally reorient, thus changing the beam transmission. While achieving practical devices is the ultimate goal, the proposed research will involve the investigation of some relevant, core fundamental aspects, such as non-linear interactions between THz and molecular or nano layers.