Mainz 2026 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

Q: Fachverband Quantenoptik und Photonik

Q 40: Poster – Photonics

Q 40.12: Poster

Mittwoch, 4. März 2026, 17:00–19:00, Philo 1. OG

Investigating Non-Hermiticity in Photonic Waveguides With Higher Modes — •Sabrina Hammel, Julian Schulz, and Christina Jörg — Physics Department and Research Center OPTIMAS, RPTU Kaiserslautern-Landau, Germany

Non-Hermitian photonic systems host a range of striking physical phenomena - such as loss-induced topological states, exceptional points, and non-orthogonal mode dynamics - that are impossible in Hermitian settings [1]. These effects are typically realized by engineering spatial distributions of gain and loss. Here, we demonstrate a fundamentally different and highly versatile approach: implementing non-Hermiticity directly in the orbital degree of freedom. Using 3D micro-printed inverse waveguides infiltrated with absorptive materials, we create photonic structures that support both the fundamental mode (TEM₀₀) and higher-order transverse modes. Certain geometries, such as an elliptical shape, allow the orthogonal TEM₁₀ and TEM₀₂ modes to couple between neighboring sites, while experiencing different amounts of absorption. This mode-dependent loss produces a non-Hermitian two-mode system without requiring spatially patterned gain or loss. Crucially, because the non-Hermiticity resides in the modal degree of freedom, it can be externally switched simply by choosing which mode is guided. This enables a new class of reconfigurable non-Hermitian photonic platforms capable of realizing and dynamically controlling non-Hermitian phenomena, including exceptional points and loss-stabilized topological states.

[1]: S. K. Gupta et al., Adv. Mater. 32, 1903639 (2020)

Keywords: photonic waveguides; non-Hermiticity; orbitronics; spatial light