PhD in Dynamic Space–Time Interfaces for High-Speed THz Beam Control

What new physics emerges when a THz interface changes on the timescale of the wave itself?
In this PhD project, you will develop dynamically modulated THz interfaces and explore frequency conversion, beam steering, and nonreciprocal propagation through electromagnetic design, device development, and THz experiments.

Information
The sub-THz regime is emerging as an important platform for future wireless communication, radar, and sensing, but controlling these waves dynamically remains a major challenge. Current interfaces can shape a THz wave in space, or tune their response in time, but doing both rapidly and with subwavelength spatial control is much harder. This limits how quickly THz beams can be steered, reconfigured, or made nonreciprocal.

In this PhD project, you will explore a different regime: space–time interfaces whose electromagnetic response changes while the wave is interacting with them. Fast modulation allows the interface to exchange energy and momentum with the field, enabling effects such as frequency conversion, dynamic beam steering, anomalous scattering, and nonreciprocal propagation.

Your research will span the full cycle from concept to experiment. You will:

• Develop concepts for fast spatial and temporal modulation of THz waves.
• Model wave interactions with dynamically changing interfaces.
• Design structures combining subwavelength spatial control with high modulation rates.
• Explore suitable modulation mechanisms, including MEMS-based architectures and alternative dynamic platforms.
• Fabricate and experimentally characterize the resulting devices.
• Build THz experiments to study beam steering, frequency shifts, and nonreciprocal response.
• Demonstrate GHz-rate two-dimensional spatiotemporal beamforming and explore its use in reconfigurable and nonreciprocal THz communication.

The project will primarily target the sub-THz regime, approximately 0.3–1 THz. MEMS-based structures are one promising route, but the broader goal is to identify and realize practical platforms that can modulate THz waves fast enough to access genuinely dynamic wave phenomena.

The project is part of SPARK – Spatiotemporal Photonic Technologies, a Marie Skłodowska-Curie Actions Doctoral Network bringing together academic and industrial partners across Europe. You will be based at Eindhoven University of Technology (TU/e) and supervised by Dr. Ahmed H. Dorrah, with Prof. Michaël Lobet at Université de Namur, Belgium, as co-supervisor.

At TU/e, you will join the Photonics and Semiconductor Nanophysics (PSN) group, working in an interdisciplinary environment spanning photonics, electromagnetics, structured waves, nanofabrication, and experimental optics.

You will spend 6 months at Université de Namur, focusing on theoretical modelling of GHz space–time interfaces, and 3 months at TNO, working on THz mode (de)multiplexing and system-level characterization. You will also take part in SPARK training schools, workshops, conferences, and network-wide activities.