Accelerated Non-Reciprocal Transfer of Energy Around an Exceptional Point

Hugo Ribeiro; Florian Marquardt

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arXiv · 2111.11220

Accelerated Non-Reciprocal Transfer of Energy Around an Exceptional Point

Hugo Ribeiro·Florian Marquardt

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Abstract

We develop perturbative methods to study and control dynamical phenomena related to exceptional points in Non-Hermitian systems. In particular, we show how to find perturbative solutions based on the Magnus expansion that accurately describe the evolution of non-Hermitian systems when encircling an exceptional point. This allows us to use the recently proposed Magnus-based strategy for control to design fast non-reciprocal, topological operations whose fidelity error is orders of magnitude smaller than their much slower adiabatic counterparts.

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Hugo Ribeiro, Florian Marquardt. 2021-11-22. Accelerated Non-Reciprocal Transfer of Energy Around an Exceptional Point. https://arxiv.org/abs/2111.11220

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