Metasurface polarization splitter

TL;DR

This paper introduces a compact metasurface polarization splitter using a rectangular lattice of silicon Mie resonators, which efficiently separates light polarizations with high efficiency and low loss, suitable for integrated photonic circuits.

Contribution

The work demonstrates a novel metasurface design that functions as an efficient, low-profile polarization splitter compatible with chip-scale photonic integration.

Findings

Efficient polarization splitting with high polarization purity.

Low-loss and low-profile device suitable for integration.

Utilizes anisotropic permittivity from rectangular lattice symmetry.

Abstract

Polarization beam splitters, devices that separate the two orthogonal polarizations of light into different propagation directions, are one of the most ubiquitous optical elements. However, traditionally polarization splitters rely on bulky optical materials, while emerging optoelectronic and photonic circuits require compact, chip-scale polarization splitters. Here we show that a subwavelength rectangular lattice of cylindrical silicon Mie resonators functions as a polarization splitter, efficiently reflecting one polarization while transmitting the other. We show that the polarization splitting arises from the anisotropic permittivity and permeability of the metasurface due to the two-fold rotational symmetry of the rectangular unit cell. The high polarization efficiency, low loss, and low profile make these metasurface polarization splitters ideally suited for monolithic integration with optoelectronic and photonic circuits.