PhD Position in Time-Reflection of subwavelength THz Waves

Project background

Our group investigates new ways of controlling and confining electromagnetic waves through time as an active design dimension. Rather than engineering wave propagation solely through spatial structures, we develop THz time-varying photonic systems based on subwavelength waveguides, where ultrafast excitations modify the optical properties of a material on the order of 1 in subcycle timescales. This approach enables entirely new wave phenomena, including time reflection, dynamic dispersion engineering, photonic time crystals and the dynamic Casimir effect. The project is jointly supervised within an ETH collaborative initiative, providing the student with regular interaction with the groups of Prof. Dikopoltsev, Prof. Scalari, Prof. Johnson, and the project partners, combining theoretical modeling, device design, and ultrafast THz experiments.

This project will combine advanced numerical modeling with experimental demonstrations to investigate electromagnetic wave propagation in time-varying THz waveguides.

Job description

• Develop numerical simulation frameworks for time-varying electromagnetic systems, modeling ultrafast refractive-index modulation, wave propagation, and temporal scattering
• Design and optimize subwavelength THz waveguides that enable homogeneous optical switching and efficient time interfaces
• Study the emergence of time reflection, dynamic dispersion, and periodically modulated wave propagation in guided THz systems
• Work closely with experimental collaborators to validate theoretical predictions through ultrafast THz pump–probe measurements performed

Profile

• Background in physics, photonics, electrical engineering, or a related field, with interest in both theory and experiment
• Experience with numerical simulations (e.g., Maxwell solvers, FDTD/FEM, coupled-mode theory, or PDE/ODE solvers)
• Interest in electromagnetic wave propagation, photonics, or semiconductor physics
• Experience with scientific programming and data analysis (Python, MATLAB, or similar)
• Motivation to combine computational modeling with experimental validation in a highly collaborative environment

We offer

• A unique environment combining theory, computation, and state-of-the-art ultrafast experiments at ETH Zürich
• Close collaboration with internationally recognized experts in THz photonics, ultrafast optics, and electromagnetic theory
• The opportunity to pioneer the emerging field of time-varying photonics, with applications ranging from fundamental wave physics to future photonic technologies