# Non-reciprocal wave propagation in space-time modulated media

@inproceedings{Ammari2021NonreciprocalWP, title={Non-reciprocal wave propagation in space-time modulated media}, author={Habib M. Ammari and Jinghao Cao and Erik Orvehed Hiltunen}, year={2021} }

We prove the possibility of achieving non-reciprocal wave propagation in space-time modulated media and give an asymptotic analysis of the non-reciprocity property in terms of the amplitude of the time-modulation. Such modulation causes a folding of the band structure of the material, which may induce degenerate points. By breaking time-reversal symmetry, we show that these degeneracies may open into non-symmetric, unidirectional band gaps. Finally, we illustrate our results by several…

## One Citation

Asymptotic Floquet theory for first order ODEs with finite Fourier series perturbation and its applications to Floquet metamaterials

- Mathematics
- 2021

Our aim in this paper is twofold. Firstly, we develop a new asymptotic theory for Floquet exponents. We consider a linear system of differential equations with a time-periodic coefficient matrix.…

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