Congratulations to Rene-Marcel Lehner

We congratulate Rene-Marcel Lehner on successfully completing his Master’s thesis entitled “Photonic Band Theory of Moiré Crystals: A Two-Scale Approach”.

Moiré patterns arise when two lattices are overlaid with a slight mismatch, for example by introducing a twist between them. In photonic crystals, such structures are of particular interest because they can give rise to effects such as photonic cavities or slow light. Understanding the corresponding band structure is therefore an important step.

In his thesis, Rene investigated how to calculate the band structure of photonic moiré crystals. Because the moiré pattern leads to very large non-commensurate unit cells, standard numerical methods quickly become difficult to apply. To address this, he developed a two-scale approach separating the underlying lattice from the larger moiré structure. Based on this, he formulated an effective Hamiltonian that allows the estimation of photonic eigenvalues around a given k-point, similar in spirit to k·p theory in semiconductors.

As part of his work, Rene also developed his own photonic band solver called Blaze2D, written in Rust. The code is freely accessible on the Blaze2D website and provides a flexible framework for studying photonic band structures.

We wish Rene all the best for the future!