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arXiv · 2509.06443

Non-Exponential Decay in Finite Photonic Waveguide Arrays

Florian H. Huber·Benedikt Braumandl·Johannes Knörzer·Jonas Himmel·Carlotta Versmold·Robert H. Jonsson·Alexander Szameit·Jasmin Meinecke
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Abstract

Open quantum-system dynamics can follow exponential decay, non-exponential relaxation, or oscillatory dynamics, depending on the system-environment coupling. We study a lattice with a boundary defect that transitions between these regimes, controlled by a single parameter. Extending the exact solution to the oscillatory case, we establish a unified theory confirmed by experiments in integrated waveguide arrays. We characterize finite-size effects by comparing analytics, numerics, and data. This provides a benchmark for emulating infinite systems and studying open systems in photonic lattices.

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Florian H. Huber, Benedikt Braumandl, Johannes Knörzer, Jonas Himmel, Carlotta Versmold, Robert H. Jonsson, Alexander Szameit, Jasmin Meinecke. 2025-09-08. Non-Exponential Decay in Finite Photonic Waveguide Arrays. https://arxiv.org/abs/2509.06443

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