# Nonreciprocal Wavefront Manipulation in Synthetically Moving Metagratings

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## Abstract

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## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**(

**a**) Schematic of a nonreciprocal metagrating (side view). Amplitudes of the reflected wave into different Floquet channels when exciting from (

**b**) Port A, (

**c**) Port B, and (

**d**) Port C. For this specific design, we assume ${\omega}_{\mathrm{ee}}={\omega}_{\mathrm{em}}={\omega}_{\mathrm{mm}}={\omega}_{0}$ and ${\delta}_{\mathrm{ee}}=2{\delta}_{\mathrm{em}}=4{\delta}_{\mathrm{mm}}=0.4{\omega}_{0}$.

**Figure 2.**Array of bianisotropic moving particles designed to circulate space waves between three Floquet channels located with 45 degree angular distance. (

**a**) Nonreciprocal metagrating. Inset shows a single inclusion composed of a loop loaded with an isolator to create one-way rotating magnetic dipole and a wire strip providing the required electric dipole response. (

**b**) Results for isolation achieved between different Floquet channels. Geometric parameters of the design: outer radius of the loop is $3.53\mathrm{mm}$, inner radius of the loop is $2.63\mathrm{mm}$, $g=0.5\mathrm{mm}$, $b=42.43\mathrm{mm}$, $a=9\mathrm{mm}$, $h=2.3\mathrm{mm}$, $dh=2.15\mathrm{mm}$, $lx=1.75\mathrm{mm}$, $ly=12.2\mathrm{mm}$, the width of the electric dipole is $0.4\mathrm{mm}$, dielectric permittivity is $10.2$, and loop is rotated for $15$ degrees in the direction shown in the figure. The structure is simulated using infinite periodic boundary conditions. Here, for the sake of simplicity, we consider ideal lumped isolators.

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**MDPI and ACS Style**

Ra’di, Y.; Alù, A.
Nonreciprocal Wavefront Manipulation in Synthetically Moving Metagratings. *Photonics* **2020**, *7*, 28.
https://doi.org/10.3390/photonics7020028

**AMA Style**

Ra’di Y, Alù A.
Nonreciprocal Wavefront Manipulation in Synthetically Moving Metagratings. *Photonics*. 2020; 7(2):28.
https://doi.org/10.3390/photonics7020028

**Chicago/Turabian Style**

Ra’di, Younes, and Andrea Alù.
2020. "Nonreciprocal Wavefront Manipulation in Synthetically Moving Metagratings" *Photonics* 7, no. 2: 28.
https://doi.org/10.3390/photonics7020028