Nonreciprocal Electromagnetic Wave Manipulation via a Single Reflection

Abstract

Electromagnetic field manipulation plays a key role in applications such as electron acceleration, nonlinear light–matter interaction, and radiation engineering. Nonreciprocal materials, such as Weyl semimetals, enable the manipulation of the electromagnetic field in a full photonic manner, owing to their intrinsic time‐reversal symmetry breaking, leading to asymmetric material response for photons with +k and −k momenta. Herein, the results suggest that a simple planar interface between semi‐infinite air and a nonreciprocal material can achieve spatiotemporal manipulation of the electromagnetic field. In particular, this work presents three compelling scenarios for electromagnetic wave manipulation: radiation pattern redistribution (with closed‐form expressions provided), carrier‐envelope‐phase control, and spatial profile control. The presented results pave the way for electromagnetic field manipulation using pattern‐free nonreciprocal materials.

Keywords

• electromagnetic field manipulation
• far-field
• nonreciprocity
• photonics