# One-Way Hyperbolic Metasurfaces Based on Synthetic Motion

## TL;DR

This paper proposes a novel method to achieve one-way hyperbolic wave propagation in metasurfaces using synthetic motion via traveling-wave space-time modulation, enabling nonreciprocal optical phenomena at practical speeds.

## Contribution

It introduces a new approach to realize one-way hyperbolic metasurfaces through synthetic motion, expanding possibilities for nonreciprocal nanophotonic devices.

## Key findings

- Demonstrates nonreciprocal hyperbolic propagation in metasurfaces.
- Enables efficient nonreciprocal frequency conversion.
- Facilitates mode transfer in nanophotonic systems.

## Abstract

Moving metasurfaces support guided waves exhibiting unusual optical properties, including strong anisotropy, nonreciprocity, and hyperbolic dispersion. However, for these phenomena to be noticeable, high speeds are typically required, challenging their practical implementation. Here, we show a viable route towards the realization of one-way hyperbolic propagation in metasurfaces placed synthetically in motion through traveling-wave space-time modulation. In addition to non-reciprocal hyperbolic propagation, the proposed time-modulation scheme induces additional exotic opportunities for nanophotonic systems, such as efficient nonreciprocal frequency conversion and mode transfer.

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Source: https://tomesphere.com/paper/1902.02653