Welcome! I am a PostDoc at the Institute for Analysis in the working group for nonlinear PDEs and my position is funded by the CRC "Wave Phenomena". In particular, my resarch contributes to the projects A1, A14 und B3.

Research interests

Some keywords:

• Nonlinear stability of periodic wave trains and variants
• Nonlinear dynamics under nonlocalized data
• Degenerate diffusion equations
• Nonlinear Schrödinger equations
• Diffusive and hyperbolic relaxation systems

Publications

• J. Alexopoulos und B. de Rijk — Nonlinear stability of periodic wave trains in the FitzHugh-Nagumo system against fully nonlocalized perturbations, J. Differential Equations 457 (2025). (DOI, Preprint) . 
• J. Alexopoulos — Uniformity in the Fourier inversion formula with applications to Laplace transforms, Arch. Math. 125, 413–432 (2025). (DOI, Preprint). 
• J. Alexopoulos — Nonlinear dynamics of periodic Lugiato-Lefever waves against sums of co-periodic and localized perturbations, Phys. D: Nonlinear Phenom 488 (2026) 135079. (DOI, Preprint). 
• J. Alexopoulos and B. de Rijk —  Nonlinear dynamics of reaction-diffusion wave trains under large and fully nonlocalized modulations (Preprint, 2025).
• J. Alexopoulos  — Nonlinear stability of periodic wave trains against nonlocalized perturbations, PhD Thesis (2025), Karlsruhe Institute of Technology (DOI)

Poster and Presentations

On the result to the FitzHugh-Nagumo system:

• Poster in Konstanz in June 2024
• Presentation for the annual CRC meeting 2023

On the result to the Lugiato-Lefever equation:

• Presentation for the annual CRC meeting 2025